I personally like www.supermediastore.com. They are a top rated site for selling what they advertise...no boggus. Check it out.
Check out http://www.digitalfaq.com/media/dvdmedia.htm for a suggestion of web sites and descriptions of each reseller. I use www.rima.com for Taiyo Yudens(it seems rima is the cheapest for these) I was using ISSI business solutions for my Mitsui purchases but due to poor aesthetic quality of the discs, may stick with the TY.