I'm sorry that I can't tell you which libraries you have to add to your classpath, maybe you'll find more information at http://struts.apache.org/2.x
If you are currently looking at 1.x tutorials you may be in a big suprise with the 2 release, it has changed radically and your 1.x knowledge may not suffice anymore.
In case you just get started with Struts I'd advice to start with 1.x and migrate later if you still think it is necessary.