This seems to be really good for finding expiring domains containing the string of characters that you enter.
Explore the millions of domains in our database. Tens of thousands of newly expired domains are added every day. Enter a keyword or phrase (with NO spaces) and click “options” for more choices. Click on the resulting domains to register while it’s still available. Expired Domain Boss is provided as a free service. Please help to keep this site alive by registering your domains through the links provided. Thank you! Gene