I think its always better to source your own equipment. Those kits are usually expensive and come with lower quality stuff. The filters are usually junk.
Get a tank at a $1 per gallon sale as previously mentioned, a used filter off of here or pick up a new Aquaclear, decide if you even need a heater, and get one of those glass hoods. You can get a light from anywhere. Or you could find the regular florescent light and plastic hood second hand from someone who upgraded and wants to get rid of them.