Handbook of Logic in Computer Science - is it worth it?
The series is a wonderful resource, but I wouldn't recommend buying it when it is available in the library, unless you knew you were going to use it for many years to come. (I have too many expensive books on my shelf that are lovely to look at, but not used much.) Many articles and tutorials with comparable contents are available on the web. These are probably a better alternative for the moment, in my opinion.