I am currently looking at the XSD utility accessed via the .Net command prompt console.
I have used this utility to generate VB/c# code from simple XML files, but currently I am have a problem with do the same using a very complex XML schema.
Perhaps it might not be an issue for you.
Oh by the way, I am currently unable to get an XMLSPY licence theregfore I am using VS. I am very pleasently surprised how rish VS is so at the moment I donot 'miss' xmlspy.