Pulling data into a content type
This is core functionality in views and very easy to do with views relationships and entity references. Essentially, what you want to do is create a new entity reference field in your location content type to reference the workers, ex: "Related Workers". You would then add the workers to each of the locations using the normal edit form.

Now in the node output, you'll have a list of these referenced entities as a unordered list of links to the "Related Workers" node which you can customize using the display fields options. 

To add these related workers (and all their fields) in a combined view (ex. the join you are referring to) you would just need to create a relationship, using this entity reference field. 

This whole process is explained in this screencast from NodeOne

http://nodeone.se/sv/node/782