It's hard to say what your body prefers as stillanimal have said.
You might have to spend a lot of money to find that perfect saddle, or you might find it at the very first one.
Charge (Bucket, Spoon), Selle Italia (Turbo, Flite, SLR), Selle San Marco (Aspide, Regal, Rolls, Concor), Fizik (Arione, Anatares, Alinate, Gobi), Specialized Toupe (143, 130, 155), Selle SMP (Glider, Evolution, Pro) are some of the most popular saddles around. Of course, I only named the more race-oriented ones, which is what I usually prefers. That said, saddles are extremely personal and you really have to go with your guts to see which one might suit you the most.