The USPTO (a/k/a Trademark Office) is the federal agency presiding over the registration and maintenance of patents and federal trademarks. While attorneys must be licensed to practice patent law before the USPTO, no such requirement exists for the practicing trademark law before this body.
The USPTO now accepts applications for trademark registration over the Internet through it's online TEAS system. CAVEAT: Be sure you understand the finer points to preparing an application before you attempt this on your own. The Trademark Office is getting better about assisting non-lawyers through the process of registration. However, you must never forget that the Trademark Office has a competing interest at odds with the Trademark Owner's interests. Specifically, the USPTO has an interest in narrowly and concisely defining the boundaries of your trademark rights. Meanwhile, the Trademark Owner has an interest in maintaining as broad of rights as possible. This tension arises throughout the registration process, from choosing specimens and selecting the wording for your description of goods, to responding to Office Actions.
Correspondence can be addressed to "The Assistant Commissioner for Trademarks, 2900 Crystal Drive, Arlington, Virginia 22202" Actual Use applications should additionally be directed to "Box NEW APP / FEE," while Intent to Use applications should be directed to "Box ITU / FEE." Statements alleging use or requests for an extension of time to file a statement of use should be directed to "Attn. AAU.
The USPTO can be reached by phone at 1-800-786-9199. Or, visit the USPTO web site at http://www.uspto.gov . Here are some site highlights.