Main Object(s) can be found in the left-hand menu under the Data section. These are completely customizable, and you just have to let us know which ones you'd like to have, and we'll get it set up for you.
Having an address for a Main Object is not required. When a Main Object doesn't have an address (i.e. Mapping Address), it will only be displayed in the list in Badger and not on the map.