Its actually quite amazing how much stuff you can find on people if you try. Two years ago I was going through a divorce and my wife at the time was trying to take all my shit and my kid. I sure the fuck didnt want to go through a long court battle nor did I want to leave my fate up to some judge so I figured the only way to get her to back down was to pull up dirt on her boyfriend. All I had to start with was his first name and an unlisted phone number.
From the phone number I was able to get his full name and address. And from that I was able to get his social security number, his criminal record, his complete divorce records, his driving record, and his employment history. I found out he had recently got a DUI and was driving without a license (with my kid sometimes) and that his ex wife accused him of being abusive.
So after getting it all together I told my wife what I knew and I would agressively use this against her. She completely backed off and agreed to everything I wanted. Damn, I should start a business helping guys that are getting divorced now that I think about it.
Anyway, to answer your question. The software programs are junk, don't waste your money. Use a service like
http://intelius.com
Depending on what you want you may have to use a few different information brokers. Some may bend the law a little and give you stuff they shouldnt, but those are the ones to use.