United States of America
For most of the participants, it will be more convenient to mail the complete set of documents to the Russian Visa Center or any other tourist\visa processing agency, using any mail carrier that you see fit. Also, you may apply for a 3-year multiple-entry Visa. Russian Embassy Visa information page: Russian Embassy.
Russian Visa Center
Russian Visa Center, the company «Invisa Logistics Services LLC» or ILS has a direct agreement with the Embassy (all of the agencies will submit applications to the Embassy through the ILS). Their agents guide you through the process of obtaining a Russian visa.
You may want to choose an agency. A few of them:
Keep in mind, those companies may suggest obtaining the letter of invitation ($50) and hotel registration ($50), however, the conference will make both of them for FREE. On the other hand, they may suggest additional handy services such as completing Visa Application Form or urgent processing.
Consular Division of the Embassy
If you are located in the same city as there is a location, you can apply directly there. Here is a Russian Embassy Visa information page: Russian Embassy
- The Consular Section of the Embassy: Washington
- The Consulate General: New-York, Seattle, Houston