European Spruce
Sometimes known by its country of origin, this is generally regarded as the best spruce for classical guitar tops. Now becoming more expensive and difficult to obtain.
Englemann Spruce
This North American wood is now starting to become very popular for classical tops. It is usually slightly softer than european spruce, with a more even, pale cream colouring. Englemann is often quoted as producing a slighty softer, more rounded sound. There is currently a good supply of high quality wood available.

Western Red Cedar
Western Red Cedar – from North America, has become increasingly popular for classical guitars and is the preferred choice of a number of makers.
Cedar is softer than spruce, and not as stiff, but good sets have nice straight grain, and a distinctive, clear tap tone. The colour is darker than spruce, ranging from light yellow/orange to darkish brown.
Western Red Cedar is currently in plentiful supply and I have some very high quality sets in stock.