If you've been looking around the bookshops, perhaps you've seen "X-Men: The Ultimate Guide", produced by DK Publishing.
Lots of pictures, summaries, factoids and profiles of the X-Men universe. The guys at DK have done quite a few of these for the Star Wars universe, and they certainly know what they're on about.
Well, the good news is that "Spider-Man: The Ultimate Guide" isn't too far away. What's even better news is that unlike the X-Men book (which was heavily influenced by the movie and the Ultimate X-Men comic), Spidey's biography is aiming for a more all-round approach, presenting Classic Spidey, through the middle years, and then also covering the Ultimate relaunch and the upcoming movie.
Look for more info here, as the release date approaches.