Don't let your enthusiasm and excitement let you get ripped-off. There are dozens of places from which you can buy "authentic" "Roman" items, only to find out later that they are not authentic at all. Please check with your unit/group Commander before buying any items.
At reenactor.Net, we list some of the BEST sutlers out there, so give them a look and tell 'em you saw their ad here!!!
Ancient Warfare magazine is the only real paper magazine, and in full color at that, about all aspects of warfare in the Ancient World, from the earliest warfare in the Ancient Near East until the end of the Roman Empire in the west. Our focus lies on the classical Greek and Roman civilizations however.
The Venetian Cat Pottery Studio -- An auxiliary member of Legio III Cyrenaica who reproduces Ancient Roman pottery, especially Samianware/Terra Sigillata as well as amphorae and other utilitarian items (oil lamps, flasks, etc.) that a Roman reenactor may find useful. Very reasonable prices and everything is hand made. Thanks for your consideration.