Just google "top SQL books", you'll find plenty. No one can tell you which one is the best for you. You'll have to decide youself. You could alway get another one if the current one isn't clear enough for you. 🙂

You could also work you way through this list:http://www.katieandemil.com/katie-and-emil-tutorial-to-70-461-querying-microsoft-sql-server-2012

And you can download SQL 2012 (Evaluation or Express) here:

http://www.microsoft.com/sqlserver/en/us/get-sql-server/try-it.aspx

I'm working my way through this aswell.

Goodluck!!