This is supposed to be a guide for players who already have a firm grasp on how to play the game and have gotten used to the mechanics of Fiddlesticks.
The aim of the guide is to provide a more reliable way to play Fiddlesticks coming out on top in team fights - ALIVE.
The typical glasscannon-sticks that I've seen may do more burst damage but never survives to continue providing CC support which I feel makes the difference from a standard Fiddle player and a great one.
Just a few wins from today using the build.

1.) Never static lane with Fiddle past level 6, he's a poor farmer you're really wanting those kills and assists from jumping into side lanes when you get the chance.

2.) Timing is essential with Fiddle, paitence really is a virtue. Wait until they're fully committed and on that instant then channel your ultimate from afar.

3.) When the game progresses to team fights and roaming the map as a team you should always be positioning yourself 10ft behind your team in the direction that is away from danger, by sticking close you're easy to target.

Pros;
Early game 1v1 domination. Great harass in duo lane.
Durable caster capable of surviving 2 or 3 v.s. himself.
Possibly the best CC in the game, 3sec fear bouncing silence.
Superb ultimate allowing him to tackle more heroes than most even without feed.

Cons;
Squishy without items
Vulnerable whilst spells are on CD
Usually targetted in team fights
Poor against durable heroes with magic resist, even early game.

The logic behind the runes is to have the flat AP to do enough damage early game to effectively harass your opponents and hopefully get the first blood. I considered tanky runes but when playing I find your items will compensate.

For the jungle route I choose the same set of runes, a high early game AP will help you power through the jungle and keep your hp max.

Dorans Ring: Standard caster starting item. This will boost you up to over 40 ability power and provide the mana regeneration to cast Dark Wind everytime it's off CD to keep up the harassing.

The next choice is situational, if you have the gold upon first going back I'd suggest going straight to catalyst which will allow you to out lane your oponent with the HP/Mana regen. upon leveling. If not don't worry the basic boots will help you survive.

Rod of Ages: Provides a whole load of goodness that will scale as you continue to play.

My boots choice is standard, you can't beat the spell pen provided. I experimented with Ionian boots however I felt they didn't match up. Always try to have a blue buff, it's invaluable for Fiddlesticks in this build as I've provided you no CD reduction.

Rylai's Crystal Secpter: Beautiful item! Not only will it dramatically increase your survivability the slow provided keeps enemies within your ultimate and allows Dark Wind to close the gap to catch them with fear.

Will of the Ancients: Your allies will love you for the buff, more importantly it will boost your drain giving you over 100% of the damage back as HP. I'm unsure if the spell vamp scales well with the ultimate but it definately helps. I tend to find at this stage underfed AD's get outhealed by your drain and it's capable of scraping back even the closest calls when combined with your 3 second fear.

Now it's time to realise games are not static. Lot's of casters? Get Banshee's Veil. The safest at this stage would be Zhona's Hourglass, recently reduced in cost it's a no-brainer for the short invulnerable period which your ultimate persistently does damage through.

Rabadons - I'd leave this until later game, Fiddlesticks has around 40% AP ratio with his spells and is capable of doing killer damage in team fights the entire time. The spell vamp from Ancients servers you better and so does the slow on the Rylai's for reasons discussed above.

A question some of you will ask - why leave fear until level 5?
Fear is a great spell but at low levels the 0.5-1seconds won't make a huge difference, you shouldn't be getting into situations where it's needed. Having Dark Wind and Drain stronger will most definately be more helpful to gain the First Blood.
Level 2-3 Drain!! It'd be a mistake to get Dark Wind again at level 3, Drain will get you the kill and keep you alive v.s. any melee that engages at this level.

Early game requires you to multi-task. You're weak without the items but you must keep them from farming.
The Early Game.
1.) Throw Darkwind at the enemy hero whenever the CD finishes
2.) Be sure to keep an eye on the enemy mobs getting the last hits
3.) Once the enemy is on 50% hp this is when you're capable of initating for the FB. Darkwind, Flash behind them, Drain, Ignite (Ignite can be casted whilst Draining). This should be enough to garuntee the kill.
Note - If you can't do 3.) continue to harass and outfarm the enemy.

Level 6, the fun begins. Harass, pretend you're going to another lane. You can go to the other lane, decide where you can profit best. Sit in that bush, ultimate out and drop everything you have on the enemy. After level 7 getting kills should be easy.

Your ultimate can be used from over walls or bushes, you can be further away than expected and still jump in by following up with a Flash. Cut off fleeing heroes by flashing after them.
BE SURE TO FEAR THE HERO THAT POSES THE MOST THREAT! Or equally fear the hero you want to take down.
Crowstorm - Fear - Darkwind - Drain - Ignite. No squishy hero should be surviving this combination.

Mid-Late game. (Always try to have blue buff, this will allow you to maintain Drain 24/7)
Later on in the game more serious teamfights begin. At this stage you should be around 3k HP and capable of taking a beating but NEVER initate the fight. Wait patiently until the enemy are close together and hopefully focusing the tank, this is the perfect time to jump in and dominate the situation. Make clever use of fear to save other carrying heroes and keep up the damage with Drain.
When you're not in a prime position hang an inch behind your team always ready to fear overextending heroes that are not a tank.

The 2nd fiddle tab represents the jungle tab.
Route
Blue, wolves, wraiths, red buff, small golems.
You're level 4 at this point!
Now it's time to attempt your first gank, be smart, enter a lane and hit once and fear instantly. This will apply the red buff slow and with some luck allow your team mate to properly engage. Fear at this level is short so use darkwind instantly to prevent them countering too quickly. Drain and enjoy. Don't panic if the enemy doesn't quiet die, even the return trip to their base is enough to give team mates the advantage.

Continue and reach level 6. The fun begins! But not quiet yet...
Fiddle is all about the element of supprise, if they see you coming, your ganks will fail. If they're not warding, awesome, place strategically timed ultimates into the lane and reap the rewards. Top and mid lanes will 99% of the time be unwarded at this point.

However smart enemies will always ward!
To avoid warding, be imaginative, can I channel over this wall? Would I reach them if I added a flash? If I take a slightly longer route would it mean avoiding detection?
- Purchasing an oracle and cleaning up wards is great for your ganks and your team. Only do this if you think you can survive and outsmart your enemy
- Have bottom lane place and anti-ward or have support purchase an oracle
- Ward key enemy jungle points and gank unsuspecting junglers for an alternative (nicely timed CV's do this work for free however)

Note that my jungling build is far less bulky than the standard build, playing smart is the key to winning the match here.
With the items, a high AP early game makes your ganks OP and late game you should consider the opponents heroes and build.
High mres - Sorc boots + Void staff.
Low mres - Sorc or CD reduction boots, high AP
Strong Ad carry? Good timing and possibly zhonas hourglass just incase.

Thank you for reading my guide on how to play a durable Fiddlesticks, please do test it out before rating up or down. I'm open to suggestions, improvements and corrections to my aweful spelling.