I've been crocheting for a year now and I must say - it's a really relaxing, mind-numbing activity! I've made a lot of dolls here and there, a head band and a hat.
I've been trying out different types of yarns too. For the time being, I've only really bought from the local 'Michael's' stores (a gigantic arts/crafts store) I think as I get better, I'll go and peruse the local yarn stores for more exotic yarns!
I've found that some yarns are definitely easier to work with and acrylic yarns actually give the worst results in terms of the look/feel of the finished product. An acrylic wool blend is a good option as it tends to break less than all wool.
Also, cotton yarn is pretty fun to use as well if you don't want all the wooly fuzzies flying around!

Here's my latest project - an 'Amineko' from the book 'Hello My name is Amineko'
Yarn used - 2 balls of Lions Brand 'Wool-Ease' Thick & Quick yarn in raspberry. I also used the same brand in 'fisherman' (the cream colour) for the paws and snout.
By using the thicker yarn, the finished doll came out pretty large! It's probably half a metre tall?