Use the services of Russian post. It is the least expensive way to send mail to US. For example, a registered letter of a small size will cost you about 70 rubles (in 2012 prices). But be prepared for the fact that this correspondence may go to the addressee long enough. For faster receipt of the letter you can use wireless high-speed mail EMS, was established on the basis of Russian post. This issue is sending at any post office.
Select non-state service delivery. There are lots of them, for example, FedEx and others. The time of delivery of such mail may take two or three days, but the cost will be much higher.
If you need to send any letter or document urgently, and to pay large sums of money you don't want to use the assistance of compatriots. Find one of the many forum of Russian immigrants in USA and ask the question there, not flying any of them in the city where you are. If the person agrees to help you, you will be able to send the necessary document for free. But consider risk - unfamiliar people can fail you and, for example, lose the necessary document.
Use the most simple and accessible way - via e-mail. Of course, this option is not suitable for those who sends, for example, a power of attorney. But for correspondence with friends and family, the Internet performs all the necessary functions - you will receive a message from a loved one quickly and free.