I learned using Apache's notes
(see Documentation) and through a lot of trial and error. I don't have any book or tutorial recommendations, but maybe others do.
Also, if you're planning to front-end Tomcat with Apache web server, check out the Tomcat Connector
documentation. That's only necessary if you are using Apache 1.3 or 2.0. If you're using Apache 2.2, you can simply pass requests through its AJP proxy module. (I learned that one the hard way.)
Tomcat is quite an "interesting" beast. Be prepared to experiment and possibly scour a few archived mail threads to get things operating the way you need them.