it might be save-money-diving.com
they did have a really good web interface and pricing, infact i went on 3 really good trips through them, but last year they disappeared. customers lost their money, some showed up to their vacation destination to find they had no reservation and no chances of getting a refund. if you do a search for them online you'll see the history and complaint.
the latest is that they may have resurfaced as topliveaboards.com.
this is all 2nd hand info from the web so i can't personally vouch for it's accuracy. but that might be the web address you're thinking of.
as an option you might want to try dive-the-world.com. i've been one on liveaboard through them and was happy with it, but that was a couple of years ago.