I wanted to find information on building trusses for my cabin and wanted to perhaps open up space in them for a loft in the construction. I sort of got the cold shoulder from a couple of truss companies and engineers when I wasn't going to buy trusses from their company. I would normally buy them, but these have to be built on site (a island) and from materials I haul in. Nothing exceptional in size 16-24' spans etc..

Are there any good articles, books or software that would give the plans and enoungh Min/Max loading, span and materials to ensure good construction and life to keep me from over building these?
Or should I spend the $250 with a engineer get a drawing on a napkin and pat on the back?