This is my build for junglewick. i've seen alot around but havent found one that looked like it would work well or did work for me in-game. so i build around them and made my own. hope you can use it well. any comments/help you can offer would be nice.

For Runes I go

Armor Pen Marks - Reason for this is stacked with quintessence's last whisper and ghostblade. nothing stops your damage tanks will run in fear.
Armor Pen Quintessence's - same as marks
Attack Speed Glyph/Seals - Not a huge amount of AS items so these will help get you there + Hunters call's HUGE bonus

For Masteries i go a simple 21/0/9 build. you can switch between the last point in the monster buff bonus or greed whichever you prefer. but late game the bonus is MUCH more effective than 1 gold per 10/s

Pros

Not squishy
can EAT squishy heros and if fed even tanky heros.
very strong with great natural life steal.
tough to kill in team fights
great engager

Cons

Disabled easy
ult stops if stunned
focused most of the time.

For items i go a heavy attack damage build with some AS and major armor pen. ill explain each item and its importance.
Madreds Razor - Of course as a jungler you get cloth armor first and this is your first item towards Madreds bloodrazor. basic jungle item. if you dont see many tanks you can always switch it out for wriggles latern for life steal and that nifty ward.
Berserker greaves - always do your boots depending on the team. if squishy and not much CC id go this but if they have alot of disables go merc treads.
Finishing madreds bloodrazor- i go pickaxe before recurve bow since your W gives good AS.
Guardian Angel- Ah such a good item. makes teams either choose to focus you quick to get rid of revive and your team destrotying them. or NOT to focus WW like simpleton's and you getting "TRIPLE KILL". the reason i say this is because i get many many triples and some quads with WW.
Last Whisper - Good to have mid-game. although get it before GA if you get fed early. and late game it gets replaced by a black cleaver.
bloodthrister - nothin to say. great damage and life steal.
Ghoatblade- EXCELLENT when your already chasing some1 whos blood scented. no escaping WW with over 600 ms!

There is NOTHING else i would see on a jungle wick and will not post anything.
Exhaust slows them and makes them deal basically no physical dmg so their weak and cant run.
Smite is every junglers pride n joy.
I wouldnt say dont change it up cause of course builds are suggestions but this is all i would use.

Well i hope you all can use this guide to your advantage. any comments and criticism are very appriciated! and i will build on what people tell me to make this guide the best it can be.