I went to Powells in Portland, Oregon, last week and had a ball. First, be advised that the automotive section has moved from the main store to the Powell's Technical branch a couple of blocks away at 33 NW Park Avenue.
The selection is even more fantastic than I remembered from my last trip. Books dedicated solely to the history of Intermeccanica, the development of the Alfa Romeo Montreal, and maintenance of your Ford Pinto can be found. I didn't go hog wild so I ended up with just two books.
The first is Analysing Formula 1. The author put together a lot of interesting and unusual stats, such as number of races before a driver achieves his first win versus the number of races between that driver's last win and his last race before retirement (Jacque Villeneuve "wins" with 132 winless races).
But the crown jewel is this Citroen ID19 Repair Manual. I really dig it, even though I'll never own an ID19.