I picked up a light box for like $50 from a camera store that's pretty great, it has cloth on both sides and above that'll soften the light coming through from a couple of built in light globes and a lamp I put above it, it also comes with a strip of cloth in the back that's a nice soft grey for a background. Works pretty well for single models, group shots, and large models.
The idea is to get light all over the model without it actually shining directly at the model and to simply keep the background plain and consistent, all you need after that is a half decent camera.
(Spoilered some huge ass pics taken with it)