  Let f be a newform of weight two, prime level p. If D is a fundamental
discriminant, define the twisted L-function L(f,D,s) to be the L-function
associated to the twist of f by the quadratic character of conductor D.
  In this paper we consider the question of computing the family of twisted
central values {L(f,D,1) : |D| <= x} for some x, by using an explicit version
of Waldspurger's formula relating the central values L(f,D,1) to the |D|-th
Fourier coefficient of weigth 3/2 modular forms in Shimura correspondence with
f.
