Corvus,
Try a search for Homemade Broadhead targets . I asked this awhile ago and my target came out great.
Basically , you sandwich foam( Boogie boards) , cardboard or whatever you can find between two 2 x 6's . One top and one bottom . . Compacting the material is 4 threaded bars , 2 on each side. Tighten the nuts , compress the material and shoot away.
I tryed cardboard but was really hard getting my arrows out[:@]So I found some boogie boards , softer foam , likeBlock foam,cut them up to fit and wha la.
Neat thing is you can make these as big as you like and there so cheap to make. The shipping on targets is more than the target itself is to get here to my door. Try a search, there some really nice photo's of the guys targets and idea's.