Trademark Info: Business Name – How to Name a Business
The naming of your business could be one of the most important decisions you will make. A name's originality and legal availability will create a real asset value of its own, as it becomes marketed and gains market acceptance. The name you choose will become the focal point of all the benefits and features that relate to your business. Customers will be able to find and refer others to it in the future.
I suggest either hiring a name creation firm or get together with your friends and/or family and throw a "name party" & have everyone bounce some ideas around. Compile a listing of names that you like the best. Once you have that list, do as much free research as you can before you delve into comprehensive research.
I listed some links where you can do some preliminary name checking. 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 I'd try them out first.
Comprehensive research consists of looking at marks that are similar in Sound, Appearance or Meaning in the pending & registered Federal AND State trademark files as well as the US National Common-Law files.
USPTO -- Go to the TRADEMARKS section
NOLO's Trademark Resource Center
Go to your state's Secretary of State page to see if they have a searchable database of business names
ThomasNet – Must register (free) to search their database