Building trusses

[boomers]

I was considering buying the "Unofficial LEGO Technic builders guide" for ideas on building bridges/trusses with Technic parts. I'm not sure this book touches on these subjects, it seems more geared towards vehicles. Does anyone have it and know if there's any content on this?
Better yet, anyone have any ideas or experience on building trusses with Technic bricks. I want to build a hangar approximately 7 feet wide ideally with no supports in the middle (i'm a bit worried about cost of the whole project so it may get reduced by a couple of feet but I suppose the construction will still be similar either way).