I was the editor of the new Visual Basic .NET Windows Services Handbook 
that was released this month. It was inspired by the original NT Services 
book, but this one is targeted at Visual Basic developers (because they 
couldn't develop services in their language before - or not very well), 
and is much slimmer (<200 pages). This is partially because it is much 
easier to build services than it was.

Have a look at it in your local bookstore, and even if you program in C# 
or Managed Extension for C++, you would gain much from this book.