Depending on your budget and location, try sketching/designing your own, checking books/web for ideas. Steel is often fabricated locally, or the nearest city. Try visiting a fab shop owner with your sketches. Not a fence company, but more of a structural steel shop. Often, square tubing or even wide flange beams for posts and framing – it can be similar in design to wood shade structures, or even have wood incorporated. I would discourage metal corrugated roofing, unless you really desire the sound effects. enjoy !