This workbook lists the tables required to populate the vendor file, and gives examples from Chicago's implementation and the TST database: https://docs.google.com/a/kuali.org/spreadsheets/d/16i2g09VkbwPny2sJi9Ipe2QWVcJEbT8B9g3eZ0FKI8o/edit#gid=1913621353
Michelle Suranofsky wrote this script to populate the vendor file at Lehigh University: loadvendorstocsv.php