Q: body panel replacements, and an easier way to do it on a budget?

I bought a 1987 Toyota pickup 2dr 4wd 5spd short bed standard cab and the out side panels on the truck bed is rusted and the driver side has the back half of the panel broken off and I want to replace both outer side panels and the tailgate and I'm wondering what would be the easiest way to replace them with out spending way to much in on a tight budget and what's is the difference between replacement body skin and body panel?.. And where would be a good website to order the panels and what all would I need as assembly kit and tools to do the job
My car has a manual transmission.