If, unlike me, you don’t have a stack of books awaiting for you to read them, you should probably take a look at this page, where Anoop Madhusudanan lists 7 free e-books. It’s always better when it’s free, isn’t it ?
To that list, I would also add two free resources about Domain Driven Design by Eric Evans. First this document available on domaindrivendesign.org and second Domain Driven Design Quickly, from the guys of InfoQ.
If you are interested in DDD, you can also take a look at the Time & Money project.