Need help with setup

[xvioz]

So I've got the gaming PC done, I've got the HTPC done (minus a couple hard drives) now it's time I go onto some audio (saving the TV for last!). It'll be hooked up to my HTPC so it'll be for music, porn, movies, porn and TV... and porn so I'd like it to be relatively loud. Always wanted to get 5.1 but the max. budget will be $1300 CDN after taxes... is that possible?

I know I need a receiver, sub, speakers, etc. I just don't know what's good and what's not when it comes to this shit.

Thanks in advance.