I guess I'm not understanding how you'll display these by. Will you be listing out the brands (Apple, Sony, etc.) and for each of them you want to get the locations? And this is all displayed on /MyPage
?
If so, you can use something like this macro in your text/xml transformation (not tested):
{%Documents[NodeAliasPath].Parent.Parent.Parent.ApplyTransformation("namespace.class.transformationname")
Then in the transformation you simply use the field macros to list out your locations like this:
<li>{%LocationName|(identity)GlobalAdministrator%}</li>