Need help choosing lighting

I am upgrading from a 46g to a 90g. I do have some live plants (swords & java fern mostly) that are looking pretty sad at this point.

I'm not sure if I'm going to start doing CO2 on my tank yet (I would, if I could ever figure out how to put my stuff together).

Can someone PLEASE tell me what kind of light I should get??? Links are also extremely helpful to me!!! Obviously, the cheaper the better. Ebay/craigslist are my friends.

Thanks!

Would a light like this be sufficient? Also, how do I know that the light doesn't interfere with the canopy on top of the tank?

http://cgi.ebay.com/48-Black-4-Lamp...5|66:2|65:12|39:1|240:1318|301:1|293:1|294:50