I'm sure I'm not the only one investing a lot of money in Google Ads, etc. It would be nice to be able to look up orders that had a referer in order to get some idea of the value of the orders coming from these ads.
I know some people set up an ad with an affiliate id so your link for the ads would be for example default.asp?PARTNER=goog - where goog is the affiliate you set up in the affiliate admin page
As the affiliate id system set with a 30 day cookie you would get a better idea of sales from ads than just referrer data.