Copying a DB or tables from a local Postgres database to Heroku
First, take a dump of the db under Windows as outlined here. This will be a human readable text file - worth a look to get a feel for what's going on "under the hood", i.e. in the background!

Then, ftp that file (as text) over to the Heroku box (Linux I presume) and do a restore from the dump as outlined here.

psql dbname &lt; infile


You may have to create an empty schema - can't remember.

Then use psql to connect to your new db. 

p.s. a word to the wise - if you're going to be using Python, Heroku and PostgreSQL, then you should be using a Linux box as your main machine - all three are Linux "natives" rather than Windows. Try it out - you'll wonder how you ever did things any other way!