Like I said, I'm only willing to invest about ~$100 on this, considering that realistically this will be the only game I'm going to want to play in the near future (I've gone the past 6 years without upgrading- I'm not clamoring for new games all the time). When I have more time and money to spend, then I will invest in a more powerful machine, which will be better than what I get here.
My question has become a bit obsolete; now that the beta is closed again, I took the time to do the research. I can actually use an Athlon 64 FX 55, which I can get for the same price. So I'll get that for a little more oomph.
The power supply won't be an issue- it's a Silverstone sst-st65fz, and I've seen people using it with dual 7900 GTs in SLI. I figured I can get that cheap ($30) so in another little while (or maybe I'll splurge now), I can get the SLI hooked up for some decent power. It's still not going to be awesome, but I'm not overly worried about it running fine on low settings.
Ram is 2 gigs. Again, not awesome, but it will do the job.
I think I've figured everything out. Thanks for the help, everyone.