Inputing your specs (swing speed, wrist to floor, height) to a website will give you a close range of what you might need but it's not exact system, getting fit by someone who knows what he/she is doing is a major plus! I just went through the Golfsmith's Smart/Fit fitting system (I am 6'6, play irons +1, 5* upright, stiff flex (I have a 3/4 swing)) and it told me I should play +3/4, 3* upright, X-Stiff), close, but not quite.
I have worked golf retail and have fitted hundreds of golfers so I can understand the $75 charge if the fitting includes time on the launch monitor, getting fit for irons, wedges and woods. Find a local pro or teaching professional at a course/driving range to see if they can fit you off a lie board. It's low tech but it will tell you exactly what you need. Should only take 10-15 minutes, maybe they won't even charge you!
PM me if you have any questions.
Kevin