Everyone has probably signed up for paid email sites. Here are a few sites to watch out for. The following paid email/pay to try sites all have the same mailing address:
Signature Surveys
Get Paid To Try
Reliaclick
Wow Earnings

This is the mailing address:
2920 Ave R Suite 146
Brooklyn, NY 11229

I make sure now that any one I sign up for does not use this address. It is very unlikely that you will ever see any money from some of them.