You should be able to get a good solid core door from any home improvement store, lumber yard, or door specialty shop. If you want it for sound isolation purposes, be sure to also get an exterior door jamb with full weather seals and a tight fitting threshold.
Maybe solid core was the wrong terminology. I want to buy a solid wood door. This place has good looking doors but the door is already pretty expensive and they want $195 shipping on top of that. I've searched but I can't find a more local option. Has anyone bought a similar door in Chattanooga area or maybe got a really good price somewhere on the internet?