Conquest of the Horde

Well, I borrowed an account of my friend, to play with my cousin on retail. What I didn't plan on, was the retail WoW folder overwriting my RP WoW folder, and now, I can only play retail. There was this guy who said he'd compile a tome of whatever files you needed to install the proper WoW for this server, but he seems to have been absent for a while, or something similar. What's the best, fastest and easiest way to get my old WoW back? I really crave some RP right now. xD

Sorry if this isn't the right sub-forum to post this in. :P

I'm pretty sure you have to re-install, If I remember correctly, Cata installs itself on to your WoW folder, or something, if you have Cata installed, then you can't play on a non-cata server.

Yeah, but what I was wondering is if anyone could compile a similar tome, and send it to me. I don't know exactly how you'd do that, but if you guys have any idea how, that'd be fantastic.