It took weeks, but I finally moved almost all my online accounts off of Gmail and behind an anonymous email proxy. It should make it easy to find out where your email address leaked from. I suggest everyone do the same. 

 If you've been doing this for a few years, don't you end up with like a hundred proxy addresses? How do you know which one you used? Are they created on the fly, like "Terry+Ledger@anonemail.com"  

 I save them in my password manager which keeps track of which websites I use it with. The email proxy service also keeps track for you. 

 And yes, generated on the fly.