This topic is old, but I'll still add my 2ยข. I usually don't really like statistical mechanics books aimed at physicists, as they are often much more focused on computational techniques than on concepts. There are however very good lecture notes by Yoshi Oono, available on his page:
http://web.me.com/oono/Y_OONO_official_site/tutorial.html
The relevant file is SecondSMR.pdf . Notice that this is a password-protected pdf file, unfortunately. The password is given on the page, though.
This book is aimed at physicists, but contains a very unusual amount of mathematical content, esp. in footnotes, with many references to the math. phys. literature. This book assumes that the reader already has some knowledge of this field. There are other lecture notes, aimed at undergraduates, on his page as well (I haven't looked closely at those, so I cannot comment on their quality):
http://web.me.com/oono/Y_OONO_official_site/tutorial_(undergrad).html
Yvan
