Warwick can do pretty much anything so. I love him. Aw. But yeah I've played him succesfully as ad carry, ap and tank and hybrid. He can do anything but in my opinion I think he only truly shines as an off-tank dps. His lifesteal is awesome and will generally net you a kill in a 1on1.

A great thing about this build is also that after you have built your Spirit Visage you can go for almost any other 2 items afterwards. I just generally go for Black Cleaver and then Atma's as they give good stats for both damage and survivability.

This is the build I normally go these days. It has excellent damage and tanking.

The masteries are across the board because it (just like the item build) nicely spreads across damage and survivability.

Runes are same again although you can change the health quints to possibly magic resist or armor.

Pros:
Great damage!
Can survive teamfights easily!
Doesn't need as much health pots to jungle!
Can do decent damage early on!
Can lock-down carries and supports!

Cons:
Harder to gank with:[
Ignite HURTS early on:[
Since your a jungler EVERYTHING is your fault if something goes wrong:[

Smite

This is your bread and butter for jungling. Anyone who doesn't take this skill as a jungler is just silly you need it for stealing/last hitting dragon,baron and pretty much any of the neutrals. DO NOT forget to use this, even if you are out of the jungle those tank minions give a nice bit of gold so pop it on them ;].

Flash

This will ALWAYS be your second skill no matter what. It is just too useful for the way the game is played atm. Flash->Ulti will almost always net a kill with the help of a teammate. And flashing over walls to escape death is priceless. ALWAYS TAKE THIS.

If you are laning as Warwick take flash as your first and then choose from either Exhaust or Ignite. Ignore the others you really don't need extra speed thanks to your E skill Blood Scent and the rest are pretty **** anyway. In SOME occasions teleport can be ok but the damage reduction/slow of Exhaust is fantastic against AD (and ap a little). And ignite will give you the edge against other lifesteal opponents and gives a nice little bit of damage to help you net a kill.

You basically just wanna GET IN and start causing havoc. Use your ulti to lock down their highest damaging champ or their support. The great thing about your ulti also is that generally when you use it your team will attack that person! YAY!

An important thing to note is DO NOT be afraid to fight with below half health you can easily get a lot of health back AND you will be mitigating enough damage to either get a kill for yourself or a teammate.

During your ulti it generally is good practice to hit them with your Q as soon as your ulti comes off. People will normally try to flash the instant you stop suppressing them and I've gotten many a kill with my Q while they flash away which is great as it wastes their flash and you get a yummy meal:D

ALWAYS wait to use Hunter's Call when you have teammates around as the buff will be given to them as well.

At level 6 YOU CAN TOWER DIVE. Quite well especially if you have a lifesteal item (Wriggle's) as long as your teammates are backing you up it be a right pain in the arse for the enemy team if you are ultying them under tower.

Simple enough. Grag your Cloth Armor and 5 Health Pots (OR 2 Health Pots and a Ward). Start on blue and use your Hunter's Call after the golem starts HITTING YOU then just smite when it hits 420. Move on from bottom to top or top to bottom (depending on what side you are on). However when you get the Lizard Buff start looking for ganks in mid and at your duo lane AND only if there are NO GANK OPPORTUNITIES then you take out double golems and recall to get items then GO GANK AGAIN. So long as you have red buff you should be attempting ganks!

I cannot stress how important ganks are. They will help your team win and give you valuable lurches in experience if they are successful. Even failed ganks will normally result in the enemy having to flash or w/e which helps your teammates out A LOT.

One more thing USE THE WRIGGLE PASSIVE and if you have some extra dough BUY WARDS. Great thing about warwick is he has so much lifesteal he doesnt really need health pots so you can ward up for your solo lane and mid to stop them getting ganked! YAY!

For those of you that are better are jungling it is much faster to start on the wraith camp, moving on to wolves THEN taking blue golem buff. You then port back to base buy what you need and go to double golems then red lizard buff. When you do this you will notice you have created a nice little loop to follow. This way is harder as you can easily be ganked and if you are not good enough you will not survive blue golem buff. BUT if you can pull this off well it can be considerably faster then the aforementioned way! :]

Here's a little walkthrough:
Start off by smiting the big wraith then using Hunter's Call to finish off the little ones. Move onto Wolf Camp and auto attack till they are dead. If you are reasonably low on health let your health pot beef you up a bit. Then go attack blue buff (it can help to kill off the two little guys first) then once you finish up your blue buff, recall and buy your stuff. Move out to the double golems (DONT USE SMITE). Go to red buff and lay everything into the big lizard and smite. Now gank check all the lanes and if there are no opportunities only then continue jungling.

When you are going for a gank you have to let your teammates know. It still fails to stun me how people NEED you to ping when you are ganking it really does but as I say do it and there SHOULD be no room for error. It certainly is a pain in the arse when you run in, do all your stuff and your teammates are farming away :[ big sigh.

Just to note although it is always good practice to gank you have to remember that YOU also have to gain levels and gold. So don't let hungry old Warwick lag behind in his experience, because it will hurt like hell come teamfight time.