You might take a run down to Renfrow Hardware in the center of Matthews on Trade St. Probably best to go during a week day when they're not busy(although they never seem too busy to answer questions)
If they can't tell you all you need to know, they can tell you enough to talk you out of it or offer to sell you the wheat and the grinder.

You might want to check out the 'Harvest' forum here on GardenWeb - grinders and wheat-to-flour topics show up every once in a while. There are people that do it. Most need more flour than they can grow in their garden so they buy organic whole grains and store them and grind as they need. Different types of wheat grow better in different regions of the country. Certains types are better for pasta making while others are better for flour. I have also heard of people raising a front yard of wheat just to teach the neighborhood about where bread comes from. It seems that the entire yard only grew enough flour to make one large loaf of bread - but it could a year by year sorta thing. There is also a small book out there completely devoted to this topic. I don't own it, nor do I know what the title is, but it is something like "small scale grain production".