I for one research products on a daily basies, in fact most of the products are designer textiles. our network is filtered, there is no reason to have access to filthy sites in order to research an ite
Different products require differnt marketing techniques.
If you are selling textiles, the marketing is differnt than selling seferoim and that is different than selling entertainment.
I would not expect the author of a Sefor to have a FB fan page an tweet out tweets of his Sefor.
However I WOULD expect someone like Avraham Fried and or Lipa Schmeltzer to have a FB fan page (Both of them do or did until recently ) I dont know if they have a twitter account or not