Happened to be at a friend's house who had a MacBook. Figured since I can always restore my iPhone in my PowerBook at home, I'd try the ringtone hack.
SUCCESS! It works. After downloading all the necessary materials, cropping my mp3's to a proper length, it took about 10 minutes to actually put the new ringtones in the iPhone.
1 problem: My other friend wanted to try after I did mine successfully. It worked. HOWEVER! He also wanted to change the incoming text sound, voicemail sound, and email sound. There are instructions for this as well, but I couldn't get it to work.
Other than that, it worked flawlessly. Having new ringtones is awesome. My roommate has one as well. Tomorrow, I'm gonna tell him "I can't find my phone. Can you call it?" Haha!