VirtueMart supports Manufacturer details but by default it just shows the manufacturer’s name in brackets, with a javascript pop-up window, that looks pretty ugly.
Fortunately we can add the logo by using the description field of the Manufacturers details and by hacking one file.
The following is tested and works for VirtueMart 1.1.3 and 1.1.4
So, open /administrator/components/com_virtuemart/html/shop.product_details.php