I expect that there has been some discussion of various "costumery" related sites on the internet, but the following link will give a person access to a site where the matter of what ancient Celtic peoples wore and didn't wear is discussed with some apparent "authority."

http://www.reconstructinghistory.com/celtic/index.html

I'm interested in knowing what the forum members here think of this and similar sites, as the author seems to speak with some reasonable authority on the matter.

The link within the page indicated by list takes you to a page where there are further links to sites about how other ancient folk clothed themselves.