I have got most of my tying instructions from "Trout and Salmon" magazine in the UK and other bits and pieces from various other magazines and books.
One bit of advice - when tying hairwing tube flies, go easy on the hair. Too much hair(wing) creates a denser profile, often does not allow the body to show through, and causes the fly to rise/swim to high in the water. Obviously, there are some, but few, exceptions to this.
The Salar patterns that you mentioned were created by Mikael Frödin. There was an article on him and the patterns he uses in a UK magazine publication. I can't remember what one, but it would have been either "Trout and Salmon" or "Fly-fishing and Fly-tying". You could get in touch with them and see if they have a back issue.
Loop Tubes - I like them but find there use more limited than others. I know some people who now fish nothing but patterns tied on Loop Tubes all year. The main advantage is in the weight for size, and they are heavy. This means that patterns to get down in the water column can be tied on them without the necessity for longer tubes. However, you have to be quite inventive with the wings to tie on them, as the bodies are too short and of the wrong shape to tie complicated, durable patterns, IMHO. With a long wing the movement of patterns tied on these can be very good, I'd eat them myself.
I, personally, prefer a lighter tube(aluminium) and a faster sinking line. The current has a greater impact on the lighter tube, giving it mor emovement in the water.
Hope this is of some help.