I'd like to supply my advertisers with a way to track the number of new customers generated by virtue of their advertising expenditure on my site. IOW, I'd like to come up with something that would be visible proof to the advertiser of the value of website advertising.
My advertisers are the hotels, nightclubs and restaurants in a resort area. The hotels are easy--I just show them the res report. Restaurants and nightclubs are a different matter.
The only idea I have is to provide users with a way to print out a small coupon that they could present to a restaurant that would give them a free (glass of wine, dessert) whatever.
Does anyone have experience with this sort of thing?