There are a lot of options out there.
Are you looking for a revolver or a semi auto?
Is this your first pistol?
If this is your first pistol try to find a range with a good selection of rentals and try out a few.
It will help you narrow down what you might like to get.
I had a friend who was dead set on getting a Glock and I convinced him to try one out before buying one.
In the end he didn't like the feel of Glocks and went with a SIG and avoided a costly mistake.
Once you get one, practice practice practice!!!!
No matter what you get if you can't hit anything with it then what is the point.
I agree with what Psychosomatic said.
I have a Taurus 608 which is a 8 shot .357 mag and it is a great revolver.
When it come to revolvers you usually can't go wrong with a Taurus, Ruger and Smith & Wesson.
Semi autos brands I would go with are H&K, SIG, Glock, Kimber, and on the cheaper side Berretta and Taurus.
There are so many good guns out there it is hard to list them all.
It usually comes down to what you like and can shoot well.
Personally I'm a big 45ACP guy and I use H&K's and Kimbers as my primary side arms.