I am not a fan of the BBQ type smokers...you can not really control the heat accurately without constant tinkering. You want an electric smoker not one where you build a fire esp for fish. The the basic key to a good smoke (esp with fish) is brine, DRY, smoke at a low temp. You do not want to cook it you want to smoke it.
For this reason, I did a lot of research on these things and have had several smokers over the years. There are lots to choose from. My first one was a little chief from LL bean. I made a lot of good stuff with that thing but it rusts out and it is hard to control the heat.
I eventually went with the Bradley smoker in all SS. The model I have is not made any more and they have gone to an all digital generator that controls temp and smoke precisely.
http://www.bradleysmoker.com/product...ectric-smoker/
I have had mine for about 8 years now and only had one minor problem in year 2 and I called them and they replaced the entire smoking unit for free. Excellent customer service and very good equipment.
If I were buying one now...I would buy the newest digital one they have, you will not be sorry. This is what you want...
http://www.bradleysmoker.com/product...igital-smoker/
They look like a small refrigerators, are insulated and it controls the heat and smoke better than anything I have seen in a non-commercial machine. Some of the big commercial smokers are incredible but they cost 8-10K+
You have to buy the wood pucks from them. They come in a lot of different types of wood for different flavors. I like alder with fish. I thought that would be a pain but it works so well and is so slick and controlled and there are no screw ups when doing it. I like the system.