I am a HUGE HUGH HUGE fan of GoDaddy but honestly their bulk domain availability isn't the easiest to use and their recent changes that make it where you can't easily copy the available domains after a bulk search is seriously a pain. Over the last month I've turned to using a site that makes bulk domain availability easy again. (http://free.whoisquest.com/) Its a tiny bit slower than GoDaddy but their 5000 at a time bulk search SAVES me soooo much time every day. My company owns over 25,000 domains currently and we are always buying and reselling so this DEFINITELY comes in handy for us. And after doing a bulk search it output (optionally) only the available domains in a easy to copy field that you can then safe (it actually has an option to save your results to a text file for easy reference, ect). But it links to GoDaddy's domain page too so I dont even have to copy and paste I just click and then add to cart and so forth. I love the site. Tell me what you guys think and if you know of a site that is easier to use. If so I want to hear about it! Thanks guys.