I have always been a big fan of the Beretta 92, it is only a 9mm but I love the way it fits in my hand. Very comfortable and fun to shoot.
I never really liked the Glock but I think that is just personal preference, the square shape of the handle would start to hurt after a while. It just doesn't fit my hand as well as the Beretta does. I have a bunch of friends who just love the Glock and find it to be a comfortable gun, I think it just comes down to personal preference.
I only shot one Sig and I dont remember what gun it was but again I didnt like the fit as much as the Beretta.
Another one you could look at is a springfield 1911, those can be had for incredibly cheap and they are very well built guns. The handle is a little narrow for my hands but I have seen some grips that would modify it perfectly and make it very comfortable.
I think it all comes down to personal preference, enjoy the process of trying out a bunch of different guns. Get experience with the variations in grip sizing and modifications that can be made to the gun. The process of playing with what is out there is half the fun. Then once you actually buy one you will be confident that it is exactly what you want.