Yeah....We decided against the coupon! No attachments or embeding in the email, just a short paragraph welcoming them to our town and a couple lines about our store/sale.
We have done alot of "private letter sales" through snail mail. There are always a few people who mail us back and ask us to remove them from our list (although we always hired a local printing company to print and mail so the address list was never from us).

All good points posted here. I have my fingers crossed for a sucessful sale but only time will tell.