Hi addicted,
Corner your driver, make sure he understands the problem, and get his cell phone number for future problems. Then, call the UPS 800 number and inform them of the problem and tell them you will not be responsible for any more erantly delivered items. Try to contact the intended recipient and push him to rectify the problem with his vendors. From then on you should not feel responsible for any more "problems".
With regard to keeping the goods, this may interest you. A package of wholesale women's clothing intended for my store was delivered in error by UPS to an adjacent children's store. That was the last anyone admits to seeing my $3000 worth of goods. The employee who signed for the box claimed the owner walked to her car with it that afternoon after saying she would "take care of it". The children's store owner says what box? And "don't bother me, just file an insurance claim". Police were less than interested in writing a report and I had to push the chief to make that happen. UPS sent an investigator but I had to raise the roof for several weeks to make that happen. The UPS station manager was less than helpful and actually lied to me in an attempt to get me to back off. She is now under UPS investigation. Despite all the "investigations", no action has been taken against any of the players and for all intents and purposes, I've lost $6000 in sales. Fortunately I paid for the goods with my AMEX card and AMEX ultimately honored my protest (after 3 denials, I was able to clarify the situation by speaking with someone in fraud dept). So my original purchase price was refunded and my best vendor, who under insured the box, took the loss.