I can recommend an Ugly Drum Smoker, I built one last year and it turns out fantastic food. Once you have got the temp stabilised it will run for hours without any attention.
I have got a Maverick ET - 73 thermometer, which has an alarm function, just in case things start to go south.
There are loads of images and idea's on this forum, and the rest of the web. They ain't called ugly for nothing, but for a minimal outlay they work superbly.
I used Weber grills to finish off inside, you have to have a bit of chrome somewhere.
Here's some pics of how I put mine together.
Iam getting together a PID controller for it, this will regulate the airflow and temp, so it can be left to it's own devices overnight. I have the PID, but getting my head round the programming is some fun.
Apparently it was developed by a chap called Minorsky, who had the idea of using a predictive controller to steer ships. He perfected it, but the American Navy didn't want it, easier to put someone on the wheel.
But this didn't go to waste, and it is widely used in refrigeration and temp control.
If you want on, there are a shed load on Ebay, But get one from China, the one's from over here are expensive.
Once I get it sorted, I'll post a thread on it. And whether it works or not, but all the other home brew one's seem to work very well.