My own opinions Briefly...
"1. Does a coil need to be in close proximity to an iron mass in order to generate an electric pulse when a magnetic field passes close by or do I only need a coil?"
You want as much flux as possible - the stronger the magnetic field the better for the coil. Iron can help but it may introduce other problems (cogging, or iron losses). Sometimes compromises have to be made.
"2. How many turns of magnet wire should be in a coil. I have 1 inch by 1/8 inch circular neodynam magnets."
It depends... how many magnets, how are they arranged - what size wind turbine blades are you planning etc. 1" x 1/8" magnets are very small to get much real power from.
"3. The flatter the coil the better? Yes/No "
It depends on the design of the alternator. In an axial flux machine it's nice to keep them pretty flat - so that the stator is thin and you get the strongest flux through the coils. You could get too thin, or too thick...
"4. What are the most common mistakes new wind power people make?"
Getting the alternator reasonably matched to the blades I think. the blades are your engine - the engine has a specific power curve (watts/rpm) - the alternator needs to be a reasonable match. Its not hard to make an alternator that 'works' or a blade the 'spins' but getting the two things matched up well is tricky. There are lts of other common mistakes too that I know of and probably lots that I don't know of (yet) ;-)
