I used the brute force method for lack anything better at the time.
I created a program that would convert the csv file to a SQL insert statement, adding in ' for strings and then posting the statement to the table.
Each table has the same structure so I didn't need to do any thing special.
The SQL statement:
insert into <table> values (xxx, 'data', yyyy)
For .mdb
http://mdbtools.sourceforge.net/
You also might be able to import the xls, csv file to Access and export from there.
I've never tried with Access but if you installed the Postgresql ODBC you might be able to connect directly to the database and copy directly.
Check out the Postgresql programming documentation on its website.
