Have a look at this free and great web tool: http://drawingtool.powertoolsfortableau.com/
it allows you to plot / draw areas on a map or background image and automatically generate the latitude & longitude.
You can then use that in Tableau to build your visualizations, super useful!
Hope this helps,
Thanks for the reply.
I want to upload a large data set with location name, country and city and then have the system populate long and lat details. the recommended solution doesn't seem to do that.
I have found other solutions online for batch geocoding but they aren't accurate enough. If I go to google maps and type in "Harvard University I get exact coordinates but any other program I uses is off by a couple of blocks. I am sincerely hoping that manual entry is not the way to go.