Google patent search. If you're more comfortable using a search engine other than the USPTO database, Google also has a free patent search engine tool that synthesizes the USPTO's information. Pro: It's more user-friendly than the USPTO's site. Con: It's in beta, so there may be a few hiccups here and there.
Fee-based services. There are also a number of fee-based services that include extensive search functions. One example: Thomson Innovation (which, like FindLaw.com, is owned by Thomson Reuters).
Searching for Trademarks
Similarly, here are three ways to go about performing an online trademark search:
Search engines. For initial screening -- and to find unregistered trademarks, which can affect your ability to register a trademark -- you can try using a regular search engine. Web searches can help you see how and where the name you want is being used.
Fee-based services. You may choose to use a fee-based trademark search engine, such as the database available through Thomson CompuMark (which, like FindLaw.com, is owned by Thomson Reuters). It boasts a range of features, including initial trademark screening, deeper screening, flexible search options, search templates, and flexible reporting and exporting for easy sharing with clients and colleagues.
Need More Help?
Of course, this list is by no means exhaustive. If searching on your own doesn't produce the results you were looking for, an experienced intellectual property lawyer can provide additional guidance on how to perform a search for patents and trademarks.