For the fan and adapter, I would get a BBQ Guru fan/adapter. Bob has the design down pat and his adapters fit like a glove.
As for the smoker, depends on your budget. It's hard to beat Big Green Egg if you're trying to justify something. Of course Vision makes a comparable version for a little less. You can get a BGE, size large, for $750 if you wait until the right sale, which includes the nest. Not sure I'd go smaller than a large. I bought my dad a large for fathers day a few years back and it's the perfect size.
Backwoods, Assassin, Stumps...all great smokers as well with varying design theory. You can't go wrong with either, but there is a price jump.
Stick burners are king, however you would not use a computer/fan on a stick burner. You sit there and manage the fire on a stick burner. Lang, Jambo, Meadow Creek....all great stick burners.