A friend who is very big into BBQ put me onto ceramic smokers. Boy does the stuff from his Big Green Egg taste good.
I didn't feel like splurging that amount of money, so I did like Alton Brown and made a flowerpot smoker. Then a while back I put a PID controller in a box and used it to control the electric coil.
I've done some great food in it since then, my favourite being salmon. The smoker has quite small capacity so I like to use a mild wood like Apple. Hickory can be a bit overpowering. Most of the smoke flavour comes in the first half hour or so.
I usually set the PID controller to about 225°F initially and keep a thermometer probe in the meat to continuously monitor meat temps. As the meat temperature rises, I back off the air temperature in the smoker.
I've put together a complete build thread on my blog together with materials and so on. I hope you find it useful. The PID controller, by the way, would also be great for controlling a 120V heating element for something like, oh I don't know, mashing malt.