How do I make my Web Service available to the public through the UDDI registry?
The information and process is available on the UDDI Web site (http://www.uddi.org). Briefly, you need to register your business with a UDDI registry. This lets you publish Web Services to that UDDI registry under your business name.
Can I use Web Services developed in other .NET languages and can those languages use the .NET services I create?
Yes. In fact, anyone can use the Web Services you create, and they don't even have to use .NET to access them. Any programming environment that can communicate with industry standard XML and SOAP over HTTP can access and use your Web Service.