We research the details of authentic apparel in a number of ways. We contact collectors, auction houses, the leagues, or any one else that we think can help us get our hands on a game worn version of what we're trying to re-create. There are occasions when we just can't locate that authentic piece and we have to rely on photos. We rely heavily on a photographers eye and attention to detail to help us do what we do. So the names Walter Iooss and Neil Leifer are very familar to us, and we're sure that their work is familiar to you. There's a pretty good chance that if there's an iconic sports photograph, one of these two may have shot it.
Check out this article and some images shot by these two legendary sports photographers. And if you're in LA, don't miss their exhibit at the Annenberg Space for Photography.
http://lens.blogs.nytimes.com/2009/11/16/showcase-78/?src=twt&twt=nytimes