I got the Aqueon delux it when it was on sale at petco for like $40. Although I thin walmart has 10G kit for like $30 or so. It has 2 screwn in incadesence bubls that can be swapped out for flouresence ones if you want live plants. You can get those also in their pet section for like $5 each. You can probably find something in the lighting section that will also work for cheaper - never tried that though because the lid has a plastic thing that the bubls have to fit in and not sure what kind would work, so I just pay the $ for the "fish" bubls.
The Aqueon one comes with a heater, not sure abut the walmart one - aqua culture or whatever the brand is
http://www.aqueonproducts.com/products/deluxe-aquarium-kit.htm
It may be cheaper to buy everything sepertly.
10G tank $13 - just the tank
Filter $20
Heater $15
Hood - various options. If you want live plants then it will be cheaper to get a setup with the correct lights but if not, craft mesh works for a very cheap lid or if you want something better - aqueon versa lids are about $15-20. This is just a glass cover.
Ebay is a good place to look for cheaper lights and filters. Just aviod the tetra preset heaters. I find they dont work for crap. I have a 50watt and it cant even heat up a 2 gallon bowl over 73