Christian points me at 5 WSDL designers that he's used. Of these 5 I have 2 (XML Spy and Omniopera) installed on my machine. In the end, I found myself using SlickEdit yesterday to create my Web service's WSDL. I was using SlickEdit for writing the C# code and it was just easy to edit the WSDL document in the same tool. Also, I find it easier and quicker to start with a boiler plate WSDL template and edit that rather than to use a visual designer like XML Spy or Omni Opera to create one. Maybe it's just me, but so far I have not yet found a visual WSDL designer that I really like. Then again, I haven't tried 3 of the 5 Christian lists.