This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
Hibernate Made Easy is probably the best book you can find for getting started quickly with Hibernate and learning the basics properly and thoroughly. However, being the author, I might be a bit biased.
The Hibernate book by Gavin King is pretty much the reference guide. You need that one, but it's very comprehensive, which makes learning a bit of a challenge. Gavin's book as a reference, and Hiberante Made Easy to give you a jump start, is a pretty powerful combination.
Check out my signature links for some free tutorials on working with Hiberante.