I am a huge fan of shooting metal plates. At my old range it was allowable, other ranges now frown on it (thinking it will riccochet I guess).
For 100 yd or more rifle it was a 12" x 12" section of bulldozer blade with two holes cut in it (blowtorch) at top. Thick chain hung from posts held it in place. You could hear the 'pang!' from where you shot and know you hit the target. Very gratifying.
For pistol, had a friend with a metal plate setup mounted on a small trailer. He would attach it to the car, bring it to the range and wheel it down to the pistol range.
You can buy individual metal targets of all types. Here is one place for example: http://www.letargets.com/html/steel3.html