I bought a Dish Networks satellite dish at a garage sale for $5 this past weekend. Before I climb up and install this thing, is it even usable?

I already have a Terk antenna installed in my attic and I'm using an RCA HDTV receiver. I can get some over-the-air HDTV channels, but I have to say that most of what I'm picking up is still analog or lower quality (some stations like PBS do come in great, BTW).

So I was hoping that with this dish I could pick up more & better stations. I figured I would point it in the general direction that everyone else in the neighborhood is pointing, but I wouldn't know what else to do. Can someone point me to some websites that have good recommendations for my type of setup?