I would highly suggest buying used, speakers don't exactly loose sound quality over the years and since they're placed in stationary positions the wear and tear is usually minimal... the only thing that lowers is the price..
There's no better bang for buck then going for a Vintage stereo set up, the sound quality you can achieve can rival that of modern set ups that would cost 5x more. You can also get some newer stuff for pretty cheap, full 5.1 systems can be had for under 150$ which makes em great for watching movies. Plus once your on this path you can always sell and upgrade as you go, just keep an eye out for what's in your area.
Vintage
http://orlando.craigslist.org/ele/3051456592.html , great looking pair of JVC floor speakers for 95$
http://orlando.craigslist.org/ele/3023817285.html, Boston Acoustics A60 speakers for 100$
http://orlando.craigslist.org/ele/3002990407.html, would definitely need some more info, but he might have a receiver/amp that can power everything
Some newer stuff
http://orlando.craigslist.org/ele/3022796606.html, Sony 5.1 system for 130$
http://orlando.craigslist.org/ele/3054805034.html, B&W book shelfs for 90$
http://orlando.craigslist.org/ele/3051851159.html, JBL floor speakers, 150$