If you know what you're doing, you often don't even need to use those pay sites. Since I do a lot of divorce/child custody type work, I've become pretty adept at digging for dirt on people here in Oklahoma County. Within about five minutes, I can know everything about any legal case you've been involved in at the District (County/State) court level, any speeding ticket, DUI or municipal offense, I can find your myspace page, Department of Corrections records, whether you own property or owe any secured debts, etc.
And if there's a real need, I have a private investigator who is excellent (and inexpensive). You'd be surprised what's public records, and for everything else, we acquire your trash