I use the fiberglass poles like KYODE does and they work great. I havbe made two pair - one for the truck and one I leave in my pop up blind case. I did buy a set of the steady stix bipod, the kind with the piece that connects them at the top. They work good too.
Wal mart carried a monopod for cameras at one time for 9.99. I bought it, took a female adapter, attached it to a wood piece, put two wood dowels in the wood piece, and it worked great. Total cost about 13.50.