USarch. The first places to check are right at your fingertips – the World Wide Web – and they're free!Preliminary Search Sites:
- The Trademarks section on the USPTO Web Site
- Your Secretary of State to see if they have a searchable database of names. You can find a listing of all states here
- Major search engines – put your product name in quotes to find exact matches; use keywords with your product name to find relevant hits
- Yellow pages
However, please be aware that this is merely scratching the surface of what's out there. Only comprehensive research will tell you if the name is truly available. But, these links are free & a great place to start, so try them first. If the name appears to be available, then you can move on to getting comprehensive research done by a private company or an attorney.