QUOTE(obender @ Mar 20 2007, 05:15 PM)

Russ,
i agree in general... however I've checked the companies you named and two out of three are included in what you called "mainline airlines" search engines.
their flights are rediculously inconvinient too (except of cause if you live in florida)...
bottom line add about $400 (round trip - $300 one way) in average to get to russia from any european country
The travel sites generally won't allow itinaries that can not be booked as a single reservation, with a single PNR (this may not be always true, just my experience). The majors also have daily flights, which is a big deal if you miss a connection. For that reason alone, a good idea for someone not familiar with international travel (probably anyone moving to the states from Russia).
Personally I think it is worth a few hundred dollars for the convenience and time-savings.
In my case, I do live in Florida, and don't mind stopping in Amsterdam along the way (I used to live in Holland, nice to visit.)
If you are within 200 miles of New York, this is a viable option as well.
The big low-cost airlines in Europe don't fly to Russia yet, just Talinn and Riga (ryanair and easyjet).
The only low-cost European carriers I know of serving Moscow or St Petersburg are Air Baltic and evolavia.com (Italy and the Baltics), and germanwings.com from Germany (these flights can be as cheap as 49 EUR). None of these sell tickets on US travel sites as far as I know of.
I'm not saying this is the best way to go, or that I would do it myself. It is very possible though if you need to do this as cheaply as possible.
I'm actually suprised there are no Moscow/New York or Moscow/Miami charters. They both seem to be popular routes. Maybe I should start a new business as a charter operator... There is probably a good market for no-frills, $450 one-ways Moscow to NY...