I am in the process of building a electric smoker out of wood and and old oven for parts. I used the door seal from the oven for my door seal. I used alot of the insulation from the oven to insulate the smoker, I used alot of the sheet metal (with enamal coating) for heat shielding... I even used the thermostatic control and the heating element from the oven to heat the smoker.
my freind bet me I couldn't build it for under $100..... he lost!!
if you want to do lower temps then take an eletric hot plate and hook it up to a line voltage thermostat for electric baseboard heating. should be able to maintain temps in the 65-95 range pretty easy. you just need to create an different way to generate smoke from your heat.... amazing smoker to the rescue!!