U.S. trademarks can be researched using the web database called Trademark Electronic Search System (TESS). TESS is a Web-based trademark database equivalent to X-Search, the USPTO’s in-house trademark database. No matter how your search goes, keep in mind that trade and service mark registration is a legal procedure and should be done in conjunction with an attorney specializing in trademark law.
USPTO Trademark Electronic Search System (TESS)
USPTO Trademark Application and Registration Retrieval system (TARR)
USPTO Trademark Assignment Query Menu
USPTO Trademark Trial and Appeal Board Inquiry System (TTABVUE)