[I promised this review a while ago. I've been busier than I realized.]
The book I use most heavily is Alan Brown's History of America's Speedways: Past and Present (ISBN: 0-931105-61-7). Brown is best known as the author & maintainer of the National Speedway Directory. America's Speedways is very different from Lost Race Tracks, which I wrote about a few weeks ago.
Where as Lost Race Tracks provides a kind of snapshot, a view into a select group of tracks, America's Speedways goes for breadth and completeness. Brown is trying to provide at least minimal documentation on every auto racing venue in the US and Canada, past and present. Some entries are very short, others run to 10-15 lines. The longer ones often have a complete list of names the track is known to have operated under, and the different configurations (surface, length, etc.) Some entries have accurate descriptions of the physical location of the track, but most do not. This can make finding older tracks a bit tough (but there are some ways of dealing with this which are not relevant to this review.) Mind you, I'm not complaining -- there's a lot of great stuff in this book, and it certainly took Brown years to put it all together.
The book starts off with a nice introduction to the history of auto racing in North America. The subsequent 745 pages then cover about 8000 active/inactive/defunct race tracks in the US and Canada, organized by state and then by the current name (for active tracks) or what appears to be the most historically significant name (or last used name) for defunct tracks. Additionally, other names are interleaved in a useful way so that if you don't have the right name, you can usually get to it ok (for example, when I went to work on my website entry for Hollywood Bowl, it having been not too far from where I live, I only knew of it as Route 66 Speedway (the name that the locals remember it by). Fortunately, the format of the book makes such research easy enough to do.