In the Twin Cities the best source for referee uniforms and equipment is Planet Soccer. There are four locations: Blaine, Burnsville, Maplewood, and Minneapolis (on Lake Street). You can also order full referee kits online from various vendors. Official Sports is the official sponsor of US Soccer and takes lead on referee uniform design. They have a large catalog of both uniforms and equipment, also feature kits that include all of the equipment you will need to referee (men, women).