Cleaned up version of uc_stock for Drupal 6. It fixes an issue with Conditional Actions that I patched over on Drupal.org. Also, adds a CA trigger for when product stock falls below the threshold, as well as a predicate on that trigger to e-mail the admin (and/or whomever you specify in the CA settings) in this case.
Separated the stock reports code from the content... slapped a couple UI improvements on (well, I think so... would appreciate feedback on this area) (You can see a screenshot here http://220.127.116.11/tmp/stock_report.ui.png )
Converted an UPDATE/INSERT block into the new-style drupal_write_record()
One thing; it depends on this patch being applied to uc_product: http://drupal.org/node/329370