We get a ~200% return on ad spend in direct web sales, not even factoring in future purchases etc. A lot of the old direct marketing catalog company principles apply. The key is getting them to shop with you a second and third time, become 12 month, 6 month buyers, and get them to come back to your site via a path other than adwords in the future. IE direct type in the URL, bookmark, print catalog etc.
We are failing if we rely on the PPC model for repeat biz, IMO, but in fact unlike LL Bean who will lose money to get you to make your first purchase, we are still profitable on 1st time customers...
That's crazy that your avatar is the bob's furniture guy. I had that as an avatar on a local music discussion forum as a joke. What a weird, small world.