Here is my current light set-up...about 10 years of upgrades and accumulation!! I'm using 3 Alien Bee strobe lights with 2 Soft boxes, also a defuser for the main strobe. My current camera is a Canon 40D DSLR tethered to either my IMac or Windows Laptop. Up running Adobe Photoshop CS3 for my editing software.
I'm constantly changing the setup to try to get that perfect picture but am not there by any means. I've been taking my own knife picture for at least 10 years, starting out with film, then going digital with the first model of the Sony Digital Mavica. Since then I've gone through Fujifilm, Nikon, and have settled on Canon. I'm happy with my 40D but am looking to upgrade to a full frame 5d Mark II at some point.
One thing that I learned early on is that the camera is secondary to taking good knife pictures...lighting is the key whether you a shooting in natural light, flood lamps, or strobes. As a good friend, who is a professional catalog photographer, said to to me, "photography is painting with light".
My studio was formally our dining room...with my wife's full support (smile if you believe that!!) we now eat on TV trays in the Den. I'm now able to not only take my own, but also work in a few knife pictures for other makers.