I use google mail, our own address, as it´s to my previous fans...
I only send out 50 at a time, but you can do this 3 or 4 times a day, I think over 200 emails sent in separate 50 bashes is spam, so you´ll have your account closed...
anyway, title, keep simple, "check out my latest deal"... and just say how cool they are and how the new vids will be just what they are looking for, then link to a click here and check out the deal and latest vids.
hoping you come through with some sales, i usually get a few on every 50 sent