First off, you should be joining a reenactment unit first, not just building an impression on your own. Almost all reenacting is unit based, in order to plan, have cohesion, jointly research, etc.
Secondaly, SOF is pretty shitty. Look at Hessen Antique, At the Front, 1944 militaria, SM Wholesale, or such. There are also very good tailors for custom done uniforms who operate on facebook, like Beauregard's Tailor.
Also, READ. Get books and read a lot. Osprey Publishing is an excellent primer, after which you can burrow into forums, collector's guides, and other specialist series.
