Targets come in all shapes and sizes.
When I focus on Fundamentals, I like to work with paper. You can download my Fundamental Focus Drill Here: Fundamental Focus Drill
For more simulated training, I love my Rubber Dummies. They take up to 5,000+ rounds of multiple calibers and come with Ar500 well built stands that make them ideal for transporting and all sorts of tom-foolery.
For Steel targets I use HalfCocked Targets. Great steel at an affordable price with great stands. Check them out here.