Is there a dialog editor for TouchUI dialogs?
I've searched around for one but can't find it.
Your favorite XML editor with the following tabs open for (partial/incomplete) reference:
Once you've knocked out a few of them, you'll get more familiar with the basic structure of TouchUI dialogs.
I would also recommend checking out a few of the Touch UI specific blog posts from Sreekanth's blog, he's got some great examples of Touch UI dialogs.