I've always preferred Sayz Me:
http://sourceforge.net/projects/sayzme/
I actually used it extensively for all the character voices in the Haunted House Candy Hunt game here:
http://www.i-mockery.com/minimocks/starween
It came in particularly handy when I was doing Death's voice at the end because, in addition to selecting a male or female voice, the program allows you to change the speed/pitch of the voices that read the text.