callasabra,
I'm in Paul's camp. Most of my limited VBA knowledge is also self-learned and a result of helping others automate Word tasks. The only book I have ever used and find it indispensable when creating a custom UserInterface (modifying the Word Ribbon UI) is "Ribbon X - Customizing the Office 2007 Ribbon."
My collection of tips (mostly related to VBA) is available here:
http://gregmaxey.com/word_tips.html