You want to use hardwoods like hickory for smoking not softwoods like cedar. http://www.smokinlicious.com/blog/?p=5
Hardwoods are made up of mostly three materials: cellulose, hemicellulose, and lignin. Cellulose and hemicellulose are the basic material of the wood cells; lignin acts as a kind of cell-bonding glue. Some softwoods like pine and firs, hold significant quantities of resin, which produces a harsh-tasting soot when burned. Because of this, these woods are never recommended for smoking! Additionally, orchard woods like apple, peach, and pecan are traditionally sprayed with pesticides in order to ensure a productive tree. Unfortunately, these pesticides are absorbed by the tree and released when burned. http://www.avalonwine.com/Smoking-Me...cipes-wine.php
Just don’t think of using softwoods like cedar, pine or fir. These will ruin your smoker and your meat.