Any good places to find old (but good condition) hardbacks?

So, I’ve recently remodeled my home office and added a big Murphy bed and bookcase wall unit. It is massive, amazing, and not nearly full enough for my literary standards. :)

I’ve been hunting for older, good condition, hardbacks from some of my favorite authors. I’m a massive Clive Barker fan (Imajica, Weaveworld, The Great and Secret Show, etc) and have been trying to track down good editions on eBay. I find it’s really hit or miss, and Amazon is really no better. Short of exploring Etsy for stuff (and my local thrift stores, which have not been remotely useful) are there any good places on the internet I should check out?

There was a time when googling for this worked, now it’s rather useless.

Thanks, all!