I absolutely love rugman.com, and if you’re a client of mine, you can skip this entry because you’ve undoubtedly heard this all before.
It’s a leap of faith to buy a rug online, to be sure, but Rugman’s prices make it worth the risk. And naturally, the more you do it, the more skilled you become.
The site is well organized, and you can search in a gazillion ways – including by specific size range, which is critical. Their customer service people are knowledgeable and will answer specific questions for you (“Is that dark blue or black?” I’ve asked more than once.) And, importantly, the rugs are returnable if you do make a mistake. Granted, it’s a pain in the neck to re-wrap and ship a rug, and you do pay the return shipping fee (about $80-$100 for a living room-sized rug), but I think it’s still worth it.