I'm not sure a tutorial would be good for this kind of thing, it's one of those skills that you pretty much have to develop on your own. There is no fast and easy way to make support structures like the one you show, they take a lot of time and patience and the ability to think in 3D. You have to use every view window, including the 3D mode, and build them one piece at a time. It might be a good idea to sketch something out first on graph paper, but I doubt if anyone who builds supports like that does that. One tip I can give you: to keep everything straigt and even, you have to keep an eye on the cursor readout, and match your X, Y & Z figures...they can be relied on 100% to place free nodes, but you also have to be zoomed all the way in so that they are placed as accurately as possible. The best thing to do is to just plunge right in and play around with the editor, don't even start a track, just build with the tubes and boards and learn your way around. I've built rather extensive structures for my rides, from supports to actual buildings, and I learned it all the hard way, marvelling at other people's structures and then looking at them in the editor and trying to figure out how they did it. Good luck...one thing: figuring it all our yourself can be a lot of fun.