Here is the equipment you'll need:
a keg: (ball lock or pin lock) These refer to what type of connectors you need to buy. Used ball lock kegs are usually "pepsi kegs" they have a manual pull tab for pressure relief. Pin Lock kegs are usually "coke kegs" which have a fuse relief at the top that you can't manually actuate, however they are a little shorter than pepsi kegs and might fit in a fridge better than the taller keg.
A CO2 Cylinder: a 5lb cylinder will last you about 5-7 kegs. Consider possibly a 10lb cylinder.
A dual gauge regulator: This is what tells you how much pressure is in the CO2 tank on the high pressure side, and what the pressure in your keg is in the low pressure side. Look for one that has a stop valve, and possibly a manual shutoff on the low pressure side, so beer won't back up in your gas line.
A Gas line: You'll need a line that goes from the regulator to the keg. Match the connector (ball lock, or pin lock) to the style of keg that you own. Connect it to the "in" post on the keg, when you open your keg this will be the post connected to the short tube.
A liquid line: Cheapest way to go is a picnic dispenser. Just a hose with a push dispenser on it. Once again match the connector to your keg type (Ball or Pin Lock) and connect it to the "out" post, this will be the post with a tube that goes all the way to the bottom of the keg.
Once you get all your equipment, you may want to try force carbonating. There are a number of ways to do it. Some people give their beer surges of high pressure, and wait for it to fall to their desired pressure. Others set the regulator to the pressure that gives them the CO2 level they want in their beer (usually 12.5 psi or so) and just leave it there.
If you want to bottle from your keg, just reduce your feed PSI to 5 PSI, and insert a 6" long hose into your dispenser so you can fill from the bottom of the bottle.
I think you'll love kegging! one container to clean and sanitize, force carbonating takes 2 days instead of bottle conditioning which takes 20-30, and force carbonating leaves no sediment... the lack of little floaties in a glass will impress those that drink your beer!