Zabasearch. You can find virtually anyone and every place they have lived in the last 20 years, birthday, address, and in some cases phone number. I found my fiance's long lost brother with Zaba. If you pay them you can get detailed information and criminal history (if any). You can also notify them to leave your info out and it even has a feature that notifies you if someone is checking your info out! There are other such "services" in existence.

The Post Office will NOT do anything about your chain letter. Yes, they are illegal but the PM almost always just tosses the letter in the circular file. If you should happened to RESPOND to a chain letter and lose money, THEN they will take some action. So many scam letters come through their hands that it is simply not cost effective to deal with them all. Same for the Nigerian scam letters.

Scams, spams and junk mail make fine mulch, fire-starters, papier-mache and I am sure they have some other benefits that the sender did not intend.