Take a look at some of Randar's posts on growing hops. He knows his stuff.
For $4, it's worth it to take a shot...even if you get nothing, they're still cool looking plants for your yard. For a "trellis", lots of folks just tie some thick twine ~20 ft high to their roof, tree, etc and let the hops climb up the twine.
If you're just a casual grower not demanding optimal yield, it really opens up the options.