Had never heard of the game until I read your question and now we're addicted!
Don't know of anywhere that has a walkthrough but I can tell you that my nine year old has figured out every level in just one day! I think it's because his childlike mind isn't as logical as mine! In other words, try everything! Some of the ways to solve the problems are completely weird - eg. in one level you squash a mouse and plant a bulb in it's carcass!
If you still get stuck, give me a shout... Clem x