I dont think there is a DIY on how to do it for the camry.
Basically, remove the radiator / fans, cruise contol, battery, headlights / corner lights / bumper lights, front grille, bumper cover, a couple bolts that hold the bumper onto the car .. drop the bumper, remove both fenders, grab a cutoff wheel and a drill and cut your old support out. Straighten your body if bent at this time. After everything is straight, dry fit it and make sure its going to work. Tack it in place in a couple spots, and re-check for squareness. If good, continue to weld the rest of the core support in place. Make sure to put something fire retardant over the motor / anything you dont want to catch fire when grinding and welding. dont go crazy with the welding. All you have to do is fill in where the Factory spot welds are. If you use the tool listed at the bottom, it will leave you a large enough hole to tack it back together.
EDIT:
You will also have to remove the AC Radiator too
EDITEDIT:
This tool also comes in handy when removing the core supports
http://www.harborfreight.com/3-8-eig...ter-95343.html