I've tried a BUNCH of different saddles, and on SadieKate's recommendation last year I am currently using the Avocet O2 40 (womens), and I really like it. It has a "T" shape, narrow nose, wide enough for me, and nice and firm, with a channel. It's not very expensive either ($60?).

Here's a link to a photo showing the channel. And on the Avocet site: features and specs

I have to say the Terry Butterfly KILLED me, although many of my friends love it. I have tried and rejected more saddles than I can remember. I liked the Selle An-atomica, except I think it exacerbated a tail-bone issue I had, so now I just use it on my trainer.

Good luck!