Are there other valuable sources I am missing? I would like to avoid a 499/month subscription to see data about the sites referring traffic to a specific URL, however I realize I'm searching for very specific and valuable data.
If you have any suggestions for ways to find this sort of information please share, I am certain just about every online company would find this information extremely valuable.
Thank you!
Not very fancy, but you can use the link: directive with Google searches.
So the query link:foo.com shows you sites that reference foo.com. Doesn't tell you anything about the quantity of the traffic going through the links of course.