Not to be unhelpful with this or anything, but it sounds like you should do some introductory reading on module development. What you're trying to do is just a slightly more advanced form of module development.

If I were you, I would start by going through some basic tutorials - not on webservices - but on how to create a "hello world" dnn module. Once you can do that, it's pretty easy to add the service and a lot of this other stuff will make more sense.