Yea I hate when I order something then it shows up as a DVD-R, which recently happened to me with my order from Secondspin.com. I wouldn't recommend ordering too much from them aside from things on the cheap you're just buying to complete a series. The Blu-Rays I got are flawless. Some of the DVDs were exrentals so that was annoying.
As for your question... I order most of my stuff from out of the country. There's always Arrow (
http://www.arrowfilms.co.uk/index.php?c=y&) surprised nobody mentioned them. Otherwise I think Diabolik is your best bet, they are just a bit overpriced.
Deepdiscount is one I check every now and then as well.