Another advantage of sourcing and processing green wood: There's stuff out there that just doesn't exist at the hardwood yard, and, if you can read wood, you can get some really nicely figured stuff for pennies on the dollar vs. retail dried wood.
I have pens out of Lilac, wild plum, domestic plum, and Serviceberry. Beautiful colors, especially the plum-- oranges, browns, pinks, purples. For pen size stuff, I rip 5/8" square pieces on the bandsaw and stick them in my greenhouse or another sunny sheltered place outside for a couple weeks, then check on them. If I'm impatient, they'll go in the convection oven. There's almost always some checking near the ends, but I just cut that off when I'm making pen blanks.
You could dry it in a more controlled manner and get more usable wood, but I probably have 1000 bf of storm downed hardwoods in various stages of processing in my yard right now, and since I bartered my labor or finished products for it, it's close to free.
Also, if you research a bit on what causes figure in woods, you can get some nice figured stuff for firewood prices. Burls around here are recognized and go for big $, but I've been able to find heavily flamed maple from firewood guys. We bought a big maple round with some heavy flaming and a huge crotch piece for $50-- too big to fit on a log splitter, so he thought he got the good deal!