I am looking at building a deck and do not want to have high maintenance but also want to keep costs low. What is the difference between trek material and composite decking and is the price difference that great?

Trex ~is~ a composite material. It is a mixture of plastic and wood. In our area, the price is about the same as clear cedar, but a lot more than regular pressure treated wood.

We built a deck last year in trex. It is very easy to work with - both sawing and with a router to round over the cut edges. The only problem was the sawdust clogs the sawdust extractors on the tablesaw more than real sawdust. And carrying the long pieces is like trying to pick up a 20 lb piece of wet spaghetti

I have not had any experience with any other composite material.

There all the same, trex is just another name brand of the same material, its all composite. So just pick a brand to go with, you'll still be paying around 30 dollars or so for a 16ft piece regardless of what brand you go with