Lynnae, I too have a New Braunfels off-set smoker. I also just finished wire-brushing the rust off my off-set firebox and repainting with 1200 degree BBQ black paint. It looks brand new. Be very carefull and DO NOT PAINT THE insides. DO NOT lubricate the hindges with WD40. Once the smoker heats up the oil will begin to burn off and the fumes will get on your food. The inside of my log-burner is a nice thick shiney gloss black from the seasonings and repeated cooks (smoking). That's what yours should look like. If you have any lose debris hanging you could use a scraper and that would be it.
My smoker sets next to my garage door, everytime I go in the garage, I get a wiff of the old iron smoker!!!!! Smells great.
Here's how I start mine. First I use a chimney starter and fill it with LUMP Charcoal, not Kingsford, the stuff that looks like it's already burned up. Crumple up some newspaper and light it. It usually takes me about 45 minutes to get the smoker up to temp. I dump the lit charcoal in the fire bix and let-er rip. I let the smoker box reach a temp of 300+ degrees to sterilize it. I then let the temps fall back down, The best I can do is maintain 250 degrees. I keep lump (lit) charcoal on the side along with my wood. Some I soak, some I don't. Depends on what I'm cooking depends on what type of wood I use. For salmon I use cherry, for my bbq beans I use misquite and hickory and oak.
Never use cedar.....
I have my stack vent open about 1 to 2 inches and my firebox open about the same, maybe a little more. Make a fire and adjust both ends and watch the temperature changes. You do have a quality thermometer in the cover don't you? If not, buy one and drill a hole and install it.
PLay with it, experiment with beans.....they're cheap.
Good luck and post your recipes here for the rest of us.