fabricator-
i dunno what part of the country you live in, but here in portland, or, home depot sells 2 X 3 8 footers for 1.63 a pop. they are all fir, and mostly clear. some even VG. if you spend some time picking through them you can get some amazingly nice lumber! (look at my recent post and i show the stock i used) i spent 30 bucks for enough wood for an 8' set (laminated). the largest downside is they are pond boards, so some controlled drying time is needed. wood framing lumber varies greatly between lowes, home depot, parr, and other yards. 2 X 3's seem to get the best stock. look around, you'd be suprised by how nice of lumber you can find, however kild dried stuff is typically not anywhere near as good of wood, but it's already "dry".
as far as i've read here, hardwoods aren't neccesarily bad. they will probably be slower to start up, but may carry that speed/momentum through a lull in wind whereas a light set may stop, then have to start up again. with the shear size of a 17 footer it may just plain make the mill "too" heavy.
if you are laminating blades, don't be afraid to let adjacent boards "f%$^&" eachother. common practice for framers. basically if you have one piece of wood with a bad warp, stick it next to another one with the opposite warp and they will cancel each other out (in theory). good luck with your decisions!