http://www.how-to-podcast-tutorial.com/21-podcast-hosting.htm has a lot of useful information pertaining to podcasting. While I was reading that tutorial, I came across this interesting tidbit of information:
Hmmm, that's very useful! That web site lets one check up to 50 domain names at once, for as many as 9 different domain name extensions.
I check web address availability using 000domains. I have to be honest. I don’t ever register domains through them, but I like their search tool because I can check the availability of several domain names all at once.
You might already have a few ideas of what you’d like your web address to be. Go to 000domains, type your web address ideas into the box, click “start searching” and it will tell you which are available.
I tend to check domain names via GoDaddy.com, which I use for registering actual domain names, but it would be an improvement on the GoDaddy site if they'd allow one to check multiple names at once, the way that the aforementioned web site does.
What would be even better would be to be able to upload an Excel spreadsheet with several hundred possible domain names and then download a revised version of that spreadsheet which would have information (in a separate column) pertaining to the availability of each listed name, with availability information about each of the different extensions (.net, .com, .info, etc.), and with a third column listing the date and time when availability was last checked. Better yet, one could subscribe to the list so that any time changes were made, a new version would be sent to one via e-mail with the most recent changes highlighted (rather than having to go to the GoDaddy.com site and manually check again on particular names in which one had an interest). Furthermore, for names which were unavailable in previous versions of the document but which had just become available, these would be flagged so that people could jump on them before anyone else got to those names; likewise, names which had previously been available and then become unavailable would be separately flagged so that one knew which names had recently become unavailable.