Is there a suggested web site/s for gaining information on the current "sales" of photographic imagery, the going "market" for such. I am not talking about the latest imagery at a Sotheby's site or what is being shown at MoMA, but for lesser tiered images. I am aware of caveat emptor and buy what one likes, however, I am searching for more than that. Trends, values, curator's evaluations and such.

For example, one could go to Amazon or such and get information/price points on a known photographer---say Karl Blossfeldt, the German photographer from the turn of the century, or perhaps a Laura Gilpin image but those price points mentioned on this site are either totally upper end or questionable.

But I would think there would be informative sites regarding the sales and purchases of the ongoing photo market as well as appraisals of imagery.

Thank you for your input & insight.

Raymond