If you're interested in J2EE Web services (i.e., exposing a session bean as a WS as per JSR109/921), you could try out the JBoss samples. That was how I originally learned about them. This page on the JBoss Wiki has some reasonable instructions.
That said, I have found JBoss to have some fairly bizarre and annoying bugs. Versions 4.0.0 and 4.0.1 had some serious undocumented limitations, these were fixed in 4.0.2. I mention this to say...don't expect a cruisey ride!
I had a quick go with them on Weblogic 9, but the Beta version I tried (about 2 months ago) had some serious issues - it couldn't generate the JAX-RPC mapping, and a couple of early issues made me decide to give it a rest.
Of course, I found a very beautiful couch. Definitely. And this tiny ad: