It is a lot simpler on 3.2.x than in 3.0.x, you will be glad you upgraded. In either case example files are in docs/jca/example-config. Look at the one for firebird or another jca adapter rather than a database example, the syntax for using our jca-jdbc wrappers is sometimes a bit different.
To deploy, put the .rar (with no jboss specific deployment file) in the deploy directory, and put the *-ds.xml or *-service.xml file either in the deploy directory or in some other deployable package that will recognize it such as a .sar. You can include the .rar in a .ear per spec, and a *-ds.xml or *-service.xml in an .ear if you include a jboss-app.xml file next to application.xml with the *-ds/service.xml file specified in a "service" module entry.