goblue: a major part of the problem is that the issues of actually fitting a factory bike to a shorter person are even more of an issue for longer/taller people, because the variations are that much longer/bigger.
while a good base is a 64cm frame (or other extra long/tall frame), keep in mind that you will need to adjust the rest of the adjustable bits: the seat/seatpost, stem angle+length, handlebar width, crank length.. these are the typical suspects. These bits will need to account for what's actually longer on your body: your thighs, your lower legs, your arms, your torso? It can be tricky.
the upside is that a good fit will make riding a very nice experience. having a large frame that doesn't fit will feel purely miserable.
my recommendation is to find a cycle club or group, or a trustworthy LBS, and find the tall people there. ask what they ride. ask what worked or didn't work for them for the type of riding they do. ask yourself what kind of riding you want to do (that will make a big difference in what kind of 64cm bike you end up with).
the common frame fittings will give you a general idea, but nothing will replace the responses you get from people in the same boat as you.
the two tall riders i ride with (one 6'5" the other 6'6") ride factory frames (a Salsa and a Trek) with the above standard modifications that fit the frame to them. they claim to be very comfortable on their bikes, and judging by how fast they go, i'd have to agree that they're doing something right!