Hello.  Unless you have had your email address hacked, there is no way someone can find your address through your screen name.  I know that with setting up email accounts, you are required to enter your personal details, but if you feel uneasy about it, you can always go into your account and give a dummy address such as "1234 usa avenue".  Be careful about signing up for things that you know nothing about, as there are all sorts of realistic emails making there way to our inboxes that appear to be real.  As a rule of thumb, if you don't know who sent it, delete it right away.  Also don't ever use a laptop to pay bills online or enter your personal details, as it is very easy to retrive personal info on them.  Using your home PC is fine, but make sure that you are always using a secured website.  Most people put there complete name in their email address which unless it is for business purposes, I would not suggest doing that.  Say you had an AOL account and you had your name as your email like: jane_doe@aol.com , if you have filled out a profile letting someone know what state you lived in, someone could go to www.zabasearch.com and get not only your address but your phone number.  You can actually go to www.zabasearch.com and see if you are in their data base and if you are, you can request your name and info be removed.  I hope this answered your question and I hope I actually passed along some valuble information as well.  Please let me know if you have any more questions.  Take care.