When I purchased the domain name, I added on the $8 for privacy registration. And yet today I received a junk email allegedly from domainsbyproxy.com inviting me to look at some web sites centered around domainestimator.com. The email said they got my contact information from Public Domain Deed Records.
The e-mail address in your WHOIS information is not you e-mail address, but it’s an e-mail address that forwards it to your personal e-mail address. This way your personal address and e-mail address are hidden, but people can still reach you if they want.
You should be able to unsubscribe to receive any e-mail from DomainsByProxy.com at the bottom of the e-mail you received.