Many of us have exchanged email addresses or posted them on our profile page. Some may have put them out in the numerous "stay-in-touch - find a new game" groups/links.
I am very suspicious when I find an email from a name/source I don't recognize. I almost always delete it without opening it.
May I suggest that, when you first email someone from Glitch, you type "GLITCH - Hello from _________" (entering your game name). I would hate to miss a message from someone but I also hate opening spam.