is a great place to check the reputation of online shops. Tmart.com isn't listed, If they aren't listed the must be new and there isn't a way to know the credibility of the source.
Two online retailers I would recommend are www.amazon.com
They are probably the largest retailers of cameras in the world, I shop at both and am always satisfied.
As for the camera you have listed, its a general brand. I would avoid it. Stick to the major manufactures Like: Canon, Nikon and the others we have listed in the forums.
40D + 70-200mm f/2.8L IS + 50mm f/1.8
Manfrotto 055CX3 + 496RC2