I'd look on ebay for them....I've seen new ones regularly go for $100-$110 shipped. If you're patient, they come up on nano-reef.com, and reefcentral.com periodically for about $100...If you're lucky you can get a used one for that price that's already been modded with a light upgrade, which is the most common upgrade for these tanks.
But then again I try not to buy anything in this hobby at new prices . :lol:
The 24w lamp that it comes with would be sufficient for some mushrooms, perhaps anthelia, and xenia. Perhaps some polyps. If you want to keep a clown it won't care what kind of lights you have on it, unless you want to try to keep an anemone for it to host in, which most folks like to do. If that's the case then you'll definitely need to upgrade your lights, because the anemone won't survive under the stock lights.
Brian