I am getting towards the end of a tortuos migration from Joomla1.5 and VM1.1.9 to current versions and apart from a couple of small matters to resolve I am just about there. One of the major issues I have that I can't figure out is how to match the URLS to the old version (for Google) - do I need to do some kind of magical rewrite in Joomla/Virtuemart or am I best trying to deal with this via .htaccess and google webmaster ? The site has some age now and it would be a pointless/destructive exercise if all the Google links out there where lost.
OLD URL - golfbuddy-gps-rangefinders?page=shop.browse&category_id=3
NEW URL - index.php/component/virtuemart/view/category/virtuemart_category_id/3
http://forum.virtuemart.net/index.php?topic=102717.0
http://forum.virtuemart.net/index.php?topic=97293.0
I have used this component very successfully - the free edition should be fine for your needs
I use it for all my redirects, it may be useful for you as well
http://www.sistemistica.it/redj.html (http://www.sistemistica.it/redj.html)