EvanGR, what is the final need?
All secondary product tables are joined using virtuemart_product_id
Check the #__virtuemart_product_customfields table with phpmyAdmin or a similar tool, if you need to code something yourself.
If you need a specific view, it is better to write a vmextend plugin that modifies the Virtuemart core code, i use this each time a need to include custom features in the virtuemart back-end