Java Servlet (.war?)

First of all I don't know where this question should be asked. If this is wrong, please move it to the correct place.

I am using IIS 5.0, Windows 2000 Advanced Server, Tomcat (newest version?). I am attempting to use an email servlet and am having a terrible time. What do I do with the .war file? Where do I put it? How do I reference it?

I am obviously not a java developer. I am an ASP developer who stays away from java as much as possible.

Thanks for any help.