Edit – I have a whole post on the Advertising Council here.
I haven’t been able to find out anything about the Advertising Council for the Ground Observers Corps as mentioned in the Supervisor’s Guide but you will find copies of the GOC brochure out there. Like the Ground Observer’s Guide, the brochures were produced in 1951 and 1955. The early one was larger and the later one was smaller and
contained updated information. From what I can tell, there were generic ones as well as ones that had specific information for various localities. I don’t know if this was an addition in 1955 or if the 1951 copy I have was a generic one or an early run without any specific information.
The brochures contain the usual rhetoric about being the “one call” that alerts the military to a possible invasion. They stress that practically anyone can be an observer but it is a serious job that isn’t easy. There are maps that show the coverage area and where observers are needed. Between 1951 and 1955, the active observation area expanded from the Northern US and the coastal areas to across the entire United Stated. More filter centers were also added in 1955. I assume these flyers would be given to potential observers and possibly left in places such as community centers, churches, schools, and of course, the local Civil Defense offices.