Ralph, here in New England the general rule is to put a jackstand at every 8 feet of hull. The stands of choice here are Brownell. Before our WS42, we had a Pearson Vanguard which was 32 feet and when the boat was on the hard there were 7 jackstands used: one on the bow and 3 per side.
Assuming that you have a WS32, which is quite a bit heavier than the Vanguard, you may want additional advice. On our WS42, there are currently 9 jackstands: one on the bow and 4 to each side.
It will be important to get the right size jackstand. However, just as important is the chain used to lock each side to side pair of jackstands.
There are two source of Jackstands that I know of that offer good advice and adequate inventory: Hamilton Marine in either Portland or Searsport, Maine; and Jamestown Distributors in Rhode Island.
Hope that helps.