Gosh, you have a lot of options for this kind of thing, especially if you'll consider online training along with pure CBT offerings. In fact, Microsoft itself is offering an increasing range of its classroom courses online, with plans to cover all of the most popular curriculum elements in the next year or two (definitely worth checking out at http://www.microsoftelearning.com/).
Other good outfits include LearnKey, Digital Think, Vigilar and so forth. But from what I see in using favorite search engines like Yahoo, Google and ask.com, the term "CBT" is getting kinda old and tired (many references are from the late 1990s). Methinks you'd be better off investigating elearning offerings instead!
This was first published in May 2004