Looking for a Good Jungler

After using Warwick for a few days, I know I need to invest my time in a better jungler. There are just so many out there, I don't know where to begin. I don't want a beginner jungler like Warwick or Fiddlesticks, but I don't know if i'm quite ready for a high skill champion. I am looking for someone... well... intermediate. Any suggestions? Please comment below. I have a lot of IP and want to spent it, so the sooner the better. Thanks!

 -Cal