I forgot to mention. A lot of the function calls are the same across the 6 version set of the API( with minor changes here and there of course ). Some people download the 6.3 SDK to learn from the samples provided there. As I say, there are difference, but they can give you a general idea of what to do and what not to do. There are some old VB.NET 6.5 beta samples here:
http://www.theinstructionlimit.com/?cat=10 - these are mostly shader demos though, but again they might help a little in learning. They won't compile right away however, because they are from an older build etc. Anyways, good luck and as I said before, don't be afraid to pop on IRC and ask if you get stuck

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