I agree on the Repti-sun 5.0. Replace them about every 6 months or invest in a UVB monitor to determine output (they are sort of pricey). Defintiely buy your bulbs online! You will pay 2x-3x as much at even the cheapest brick & mortar store - shows don't usually have great breaks either (at least not around here). reptiledirect.com and retpiledepot.com are two places that sell them for about $18 regardless of size. I personally would stay away from the Mercury Vapor bulbs for now. You can evaluate when the chams are older, but believe me, they give of a LOT of heat and blow out frequently. For the $$ ZooMed reptisun 5.0 is the way to go 
http://www.reptiledepot.com/
http://www.reptiledirect.com/index.asp?PageAction=VIEWPROD&ProdID=39
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Chameleon Help & Resource Info
0.1 Veiled Chameleon - Luna. She's now hanging from her big jungle gym in the sky
1.0 Beardie - Darwin
0.2 felines - Kyndra and Lita
0.1 African Clawed Frog - Skipper
0.1 Mad. Hissers and she's back!
0.1 Chilean Rose Hair Tarantula - Rosa Leigh
0.1 Goliath Bird-Eater Tarantula - Natasha
?.? Pinktoe Tarantula - no name yet
