I've found that with my board bows, the handshock comes from too thick of wood. A good design for the board is the pyramid style bows. About 2.5" thick right above handle down to about a little less than a half inch for the limb tip.
I have my first hickory board bow hanging on the wall and shoot it now and then. Boy does it stack and the handshock is terrible, but it was my first bow.
Nowdays I use staves of osage, elm, or sometimes hickory.
Couple good books to get if you are into bow building, Trad. bowyers bibles one, two and three. I also like the Reginal Laubin Indian archery book.
A few good sites have already been mentioned, Paleoplanet excellant, PA is good and they have a monthly bow build off, also try
[url] Tradgang.com[/url] bunch of good folks over there.
If you go to Tradgang, ask for a guy named Tim Flood. He makes really good board bows, he follows the Tim Baker style, wide with little tips.
I prefer 60" osage flatbows backed with sinew in the 65lb range. They are quick, strong, and I have found the the cast is just as good as most production recurves.
Frank
PS - the bow in my pic is a 48" osage recurve that I backed with 7 layers of deerleg sinew. It pulled 48lbs at 27".
I donated it to the St. Judes auction a few years back.