Wow, not many Canon DSLR users in the US then?
I've got a Canon EOS400D (Rebel XTi?) which is mainly used for general photography tasks & product photography, it's got the kit 75-300 (Crap), kit 18-55 (good) & a separate EF-S 60 macro lens. The sensor size is a bit on the small size in comparison to the current crop of cameras, but it's still the photographer that's the limiting factor, rather than the equipment
I do way more product photography these day than model photography, but they are quite similar disciplines. For product shots the single best thing I have is a USB cable - nothing amazing in itself, but it allows me to do tethered shooting in combination with Canon's EOS Utilities (free with the camera & to download). Tethered shooting is EXCELLENT, it allows you to take a shot & get an instant full screen preview, make quick adjustment to the cameras setting (from the laptop) & re-shoot - it's a huge benefit when your trying to adjust things to get lighting, exposure or the likes set up. Tethered shots are generally done in RAW for easy & lossless adjustment pre edit.
The macro lens is superb at doing it's job, the only downsides being it's price & the fact that's it's slightly less versatile that I expected.
A Giottos MTL tripod & some flouro daylight bulbs are my other bit's, I did have a light tent, but it's been relegated to the back of a wardrobe somewhere & it was just a pain in the ***.
One of these days I would like to move onto a full frame Nikon with Live View (if they do it), but between the expense of the camera & new lenses it may be a while away...