There are many but also the kind of stub you generate depends on the framework/spec. you are using.
Java6.0 comes with a wsimport utility to generate the stub. Check the JAX-WS client side section in this
JAX-WS tutorial
If you are using JAX-RPC each server has a little different way of handling. In the case of Axis you will have to use the tool coming with Axis.
For generating web service from wsdl you can again use wsimport. See the "JAX-WS Start From WSDL-doc style" section at the above link.