You can also go with Autocheck as an alternative to Carfax, especially if you're concerned about any accident history. CBS Atlanta did a story on what Carfax missed and the crash data that Autocheck had in their report. I tried to find the story but it appears to no longer be available.
Here's an article that may be of interest:
http://www.thetruthaboutcars.com/201...-vs-autocheck/