Hello Warston
Cold smoking is a method of preserving and flavouring food,meat fish etc,without cooking it,so the finished product is essentially raw.
Smoked salmon is probably the most famous cold smoked product.
The home cold smoker uses all sorts of things in which to smoke their food,old(cleaned!!) oil drums,sheds, old freezers,just about anything that will contain the smoke-I use a miniature plastic greenhouse.
Cold smoke generators can be made or bought,I use this type :
http://www.macsbbq.co.uk/CSG.html
Google "coldsmoking" & you'll find all the info you need.
Good luck
Give a man a fish,and you feed him for a day.
Teach a man to fish,and you won't see him again for the rest of the season.