HTG and ebay are both good places for low pricing, but youll sacrifice quality generally. A place worth checking out is plantlightinghydroponics.com. I havent compared everything they stock, but I know Quantum BadBoys and 1000w digis were a substantial amount cheaper than anywhere else..ebay included, and htg doesnt even carry Quantum products. Last, if you live in or near a medical state craigslist is awesome! I pieced together my veg AND flower setup for what you would pay for a 1000w set up in a store.

the cheapest place to buy lights

ultralohydro, they are where its at:sun

moregreen

takes green to grow green