TDD can only really be learned by doing it. Katas are an excellent way to get it down.
http://codekata.pragprog.com/
don't forget the classic http://www.butunclebob.com/ArticleS.UncleBob.TheBowlingGameKata

>I'm working on it, too. I think I have a decent idea but I'm just not polished enough yet. I do feel I have a decent testable architecture down, but when I sit down to try TDD on my controllers it feels like I get writer's block.