FadingAway, what type of Windows do you use? If it's XP you have cyrillic already, you just have to activate it. However the hard part is to remember the keys- in classic layout they are VERY different from english (latin).
The best link I know to solve all that:
http://ourworld.compuserve.com/homep...or/kbd_eng.htm
You'll get anything you need to know+ needed software from there.
Echoed, :don't be so sure about surprising Russian people with your looks+ability to speak russian- remember, several former Soviet Republics( such as Kazakistan) populated by Chinese-looking people who are all fluent in russian!
And on a subject of "Can an Americans speech pass as authentic in Russian if they're fluent?" the answer is -NO.
I've studied english in St.Petersburg University (That is St.Petersburg Russia, not Florida) and we've had number of exchange students from various universities in the States, (Harvard among others) however NONE of them was even close to being able to fake russian accent to a plausible degree, even the best last-year students...