So guys as you may have noticed this guide just went through a major overhaul. Attack speed Lulu was nerfed into oblivion and with the start of season 3 I figured it was time for a remastering. So anyway over the last 9 months I have played Lulu every way imaginable, support, ap carry, ad carry, jungle, top lane, attack speed, literally everything. What I have found is that if you play her heavy AP tanky Mid she becomes one of the most powerful champs in the game. Lulu is a champ that is unexpected to do well, and most mid enemies don't know how to combat her. Every time I enter a game, people are surprised at me going mid (especially in ranked) but once I start to carry (which happens very early) people realize how viable ability power Lulu really is. Lulu with my build ends up doing plenty of damage while still greatly helping the team in fights.

Right now this seems to give Lulu a good balance of all the things she needs most. Mana Replenishment Seals make spell spamming all the easier allowing you to harass with Glitterlance and Help, Pix! as often as you want. Ability Power Quintessences allow for a dominating early game giving your Glitterlance comboing with Help, Pix! an amazing harass ability. Glyphs of focus are standard for most champions, with the cooldown reduction it allows you to hit your spells more often allowing for a better ability to save, be saved and harass. Magic Pen Marks are wonderful for the early damage as most people only have a little bit of magic resist in the beginning.

For masteries I went 22/8/0. The standard attack magic masteries plus Havoc, spellsword, and Summoner's Wrath added in. The reason once again why the attack masteries are higher up is due to the fact that this is not a support build, and you want to deal the most damage possible. The eight points in defense allow for you to be much tankier due to the fact that Lulu is a naturally squishy champion. The health regen and magic resist really helps for your midlane game.

Before you go off, as most people do telling me how wrong the build is I want you to try it for yourself even if its just in a bot match, after that feel free to tell me how you felt, as I said before I am open to suggestion just remember for this build we are not trying to build her as a support. The thing I'm learning about that build is that it is similar to a heavy AP champion build. You start out with a boot of speed and pots as it makes your early skill shot dodge much more powerful. I next build into a Kage's lucky pick, this is kind of a guilty pleasure of mine some people don't like it but the added gold really helps build into Lulu's more expensive items. Buy your tier two boots next, depending on how the game is going or how you are playing Lulu, it will change which boots you should get, you could get Sorcerer's Shoes or Ninja Tabi but I seem to have found that the Mercury's Treads work the best. Next you start to build into the item that all tanky Lulus, even the support one's should have, Rod of Ages. This item on Lulu gives her ability power, health, and mana making it a perfect item for her no matter how you are playing. Next in order to make her more tanky you buy Rylai's Crystal Scepter, with that and Rod of Ages you are tanky enough to survive almost all ganks and still put out a ton of damage. Rabadon's Deathcap is a MUST for all ability power champs and with it you can deal massive damage with Glitterlance and Help, Pix!. The next two items, Liandry's Torment, and Morellonomicon, are there to play around with as in most games you will not even have time to get those items.If you want to you can also upgrade your boots again to whatever you prefer. It is all situational or if you have a preference. Very very rarely will you have the chance to build them all and by that point you will be so fed or farmed that it wouldn't matter. I have tried all of the items with her and although I only ever got them all a few times they all seem to work well no matter what order you build them in. If you think another item would work better comment and I will test it to see how it works.
*Update

This has been a topic of debate recently on which skills to max first and which to leave. For this Glitterlance should be maxed first, followed by Help, Pix!, then Whimsy. However in order for this to work you have to be able to hit with your powered up Glitterlance.
[*] If you are having trouble landing a Glitterlance you should use Help, Pix! to attach Pix to the enemy champ and Glitterlance while attached to the person you want to hit, allowing for an easy point blank hit. Glitterlance gives you a great early game harass with the slow and the mass amount of damage it can do.
[*] Whimsy is one of the more fun abilities, with the different ways you can use it. Being able to transform an ulting enemy champion into a cat is not only fun but also extremely effective, in that it helps your teammates or you kill the enemy. If you are getting pushed you should try to save Whimsy for when they dive you, quickly Whimsy them after they hit you on tower and you will very easily slay them. Also when you cast it on yourself or another teammate it allows you to be sped up and raises your AP based off of its rank 20 at rank 1 increasing by 10 on each level up. In order to surprise your enemy and deal good damage, wait till they through a spell on the minions then whimsy yourself uping your speed and ap, run at them and quick thrown a Help, Pix! / Glitterlance combo to do a ton of damage.
[*] Help, Pix! is good for vision, assisting teammates with your shield, and just landing a burst of damage on the enemy. When you learn how to use it appropriately in can be a very good spell to have. If you attach Pix to the front of your minion line or on an enemy or enemy minion it doubles your range on Glitterlance allowing for a very strong harass ability by being able to fire Glitterlance from wherever pix is.
[*] Your ult, Wild Growth is one of the most fun in the game in that it can be cast on any champion who is being focused giving them the edge in any team fight. You want to use it on your main damage dealer or whoever is being focused in the team fight. It can really turn around any fight if played right. Her spells are a ton of fun and if played right can help to win any game.
[*] Your passive, Pix, Faerie Companion is fun but not as useful when not building AD or attack speed. But it does allow you to do more basic damage to champions, so if you have the opportunity to poke with it do it.

Since Lulu is being played mid Ignite is very powerful for finishing off enemies. The other ability is up to you I personally love Flash and the mobility it gives me to get in or out of a fight. However if you prefer Teleport or Ghost both of those can work well with Lulu. I would not give her Clarity with all the mana regen you have and I would not give her Exhaust because of her slow ability. [

In team fights Lulu should not be focused due to how tanky you are. But still try to stay at the back with the big guys in front of you. Having Wild Growth in team fights can really turn things around make sure to focus and think about who to use Wild Growth on before the team fight. Spam Glitterlance, give out shields, and turn the major damage dealer into something adorable. If you want you can also Whimsy yourself and use Help, Pix! to do more damage. Do not use Wild Growth to start a team fight unless the carry is being focused. Wait and see who is tanking damage and then when all the team is near pop your ult popping up and slowing any enemies near them. If you do these things team fights will become very easy for you.

Lulu is a great champion to play and can work really well when played right. As this is my first build I'm up for any suggestions you may have. I hope this guide can help you show people how good it can be. I recommend you play a bot match before jumping right into a normal game with her as its a different play style and you will want practice. Hopefully you enjoyed the build and will comment or upvote, I take all suggestions seriously and I will be constantly editing this so feel free to tell me anything. Even after nerfing her into the ground we will still do whatever we want. :)
Thanks guys :D
Sorry I took so long to re-update but after this giant overhaul I think you will be very happy.
Here are some examples of myself playing this new lulu build in Ranked.