If you're going into a reputable bike shop, trust their guys to order you the right overall frame size, usually based on your height and inseam. Your stack, reach, etc. is all adjusted after you get the bike. It may involve ordering a longer/shorter stem, raising/lowering handlebar angle, seat height adjustment, cleat angle adjustment, etc.
The only time it gets a little tricky is 1) if you're between sizes, and/or 2) you have atypical measurements (like a long torso for your height, or long legs for your height). But talk to the reps in the shop (even if it's an online shop, chat with them over the phone). A bike is too important a purchase to rely solely on online tools, especially if it's your first time.