I've read (most of) Java Concurrency in Practice by Brian Goetz, which is very good.
There is obviously a Java-based theme running through the book (using Java specific implementations of threads, locks etc.), but pretty much all of the principles can be applied to other languages.
The author's home page contains a list of articles he has written, some of which include threading related stuff. Maybe start there and if you like his style, buy the book.