Free: Contests & Raffles.
I've got a set of black diamond carbon z poles and they are awesome. My previous set was a pair of the titanium goat poles that were amazingly light and worked awesome as a center pole for my shelter but the black diamond poles are a lot more stout and the wrist straps help a lot when you're really pushing hard up hill. Trekking poles make all the difference, I suspect if you buy a cheap set you'll just be upgrading soon because they make a huge difference