The CZ75b is a world-class pistol at an unbeatable price. The ergonomics are excellent, it's extremely accurate and as reliable as anything else made. It just feels good in your hands. It's all steel, so it's kinda heavy for carrying - and it typically takes 300-400 rounds for the trigger to smooth out at first. But after that it's very nice.
Personally, I prefer the Sig 226 because the trigger has a cleaner break to it and I shoot it a little better than the CZ. It does everything well and is beautifully made - for me it's the ultimate combat pistol. It's a pretty expensive gun for a newbie, but you sure wouldn't need to buy anything else. You will anyway, because guns are like that, but you wouldn't NEED to.
The Glock 19 is also an excellent pistol and will do pretty much everything the other two will - plus it's totally indestructable and brilliantly designed. But the grip angle is strange, and it's very difficult for me to tell when the trigger breaks, and I don't shoot them well. But there are plenty of guys out there who do. Rent one and see if it's for you.