www.tennisinsight.com is similar to tennis.matchstat.com - gives you the breakdown of a match including the H2H, and recent results for each player.
www.tennisform.com - It's a pay service. I'd never buy it, but it's useful to look at the 'previous match notes' archive. You can get some good info there, whether it be an injury doubt, a couple of player quotes, or a summary of a players style.