I don't know anything about group cohomology and I'd like to.
What is the best text to learn this subject?
I'd prefer as soft an introduction as possible - that is, lots of motivation, lots of examples, slow moving development of intuition. (Something like Simmons' Intro to Category Theory, if you've read that.) I have a background in finite group theory and some character theory. The text should actually show how to compute group cohomologies, preferably not too far in, something I have not found in the group cohomology books in my University library.
A textbook would be great, but good lecture notes or papers would be fine too.