(*but were afraid to ask)
My good friend and former Yahoo! colleague, Luke Wroblewski, has just published a most excellent book called Web Form Design.
Forms are everywhere. And when something is so ubiquitous, it tends to get absorbed into the back of our consciousness. Luke takes the lowly form and shines a spotlight on form usability. This book is full of best practices, tons of examples and lots of great insight from a dozen or so other leading web practitioners.
And hey. I can get you a 10% discount. Just go to Rosenfield Media and apply the code BSCOTT. Just enter it on the last page of checkout. You will save 10% and get a great book.