I would first start off by saying there is not a lot of content in your individual product pages.
Go for the gusto and get some relevant content in for each of your products... Such as
http://www.officesupplystop.com/Shar..._p/al100dr.htm
Only says what it works with. It does not say anything about the toner, how good it is, why I need that one, why it is better than office depot's... Etc.