I just happened to stumble across this small countertop hydroponic planter in my online wanderings this afternoon.
http://www.gardeners.com/buy/c...
Starting out with this might give you an idea as to what exactly it entails.
From one friend who tried (and gave up) to grow veggies hydroponically at home, I gather it's an expensive, complicated set-up and quite high-maintenance. Also if you don't have a large enough space with excellent natural light - large south and west exposure windows - for at least 6 hours of the day, you're going to need to use artificial lights as well. More expense for electricity.
Here's another informative site that doesn't try to sell you anything
http://www.homehydrosystems.co...