I found this on a legal website outlining the law for anabolic steroid users:
"Of course, anabolic steroid distribution is investigated in a variety of other ways. For example, monitoring news groups and chat rooms on the Internet has become a common approach of federal agents. Trying to sell or buy steroids over the Internet can be an excellent way of getting oneself arrested. It is always best to assume that anyone looking for steroids on the Internet is an undercover police agent. Federal Postal inspectors also monitor the U.S. mails. Suspicious packages coming from overseas or Mexico can be examined. Among domestic parcels, those from California and the Southwest to sites on the East Coast reportedly have a higher probability of attracting attention. Once suspicion is aroused, inspectors will investigate records of prior packages involving the points of origin or destination. If illegal drugs are found in the mail, the U.S. Postal inspectors will often arrange a "controlled delivery" of the package to the designated recipient. If the package is accepted, agents will immediately enter with a search warrant to look for additional drugs. Obviously, sending or receiving anabolics through the mail is risky business."