It depends what you want to do. Do you want a german WWII theme or are you interested in a quality portrayal?
If the latter I would spend alot of time on this forum:
http://forum.axishistory.com/
Alot of great resources there. Try to pick a specific unit/year and you can get a more accurate of those troops. Alot of things changed between 39-45 and it can be hard to make an impression without a specific reference. You can even look at getting into some of the smaller items that make a good impression great (slick back hair with brylcream, soldier pay book, period foods in the breadbag etc...).
A few years ago there were some decent replica helmets avalible in HK through ebay...with a cover on they look convincing enough for airsoft (wore one in real reenacting even).
Also look into ways to break your gear so it actually looks right...too many impressions (from any war...) look sparkling clean and out of place.