Check out CraigsList. I am always seeing old kegerators or kegging supplies (regulator, CO2 tanks) listed there for a reasonable price. Pick up a STC-1000 from ebay or amazon for under $20, and you can make your own temp controller(check the DIY section for instructions) for a reasonable price. You can also often find old chest freezers/refrigerators on there for free-$50 just make sure they work before picking them up as they are not fun to dispose of otherwise. The part that really gets you is when you spring for the nicer parts. Multiple pressure regulators, Perlick taps, fancy tap handles, etc. Note that we tend to reccomend 10 foot lines or so, as you will notice a plethora of posts about foaming problems which 5 foot lines.
Beware though, kegs seem to want to multiply like bunnies. That additional addiction can be a touch painful to the wallet.
Additionally, you can go for pin lock kegs over ball lock and save up to $20 per keg. They arent worse or better, just different quick disconnects. Additionally, if you can find some good ones in a scrap yard or other place to find them legally, you could also go with sankey connections and use commercial style kegs.