The user registration page is already set to store the IP address of the person registering.
In the insert record behavior the IP column is bound to the Remote Address variable under the Server collection in the bindings panel.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.