Last week, we had the author of TDD for a Shopping Website LiveProject. Friday at 11am Ranch time, Steven Solomon will be hosting a live TDD session just for us. See for the agenda and registration link
Depends what kind of handheld you're talking about. For PocketPCs or Symbian devices, Java is definitely an option, it's here now. For Palm devices it's just starting to be viable: you really need to use a special product like IBM's J9 or esmertec's Jbed to do serious work. Sun's Palm solution right now, MIDP4Palm, is simply not good enough.