Inventory Tracking Question

[amocj]

I'm using Virtuemart 2.0.1 and can't figure out how to track inventory like I want.  I can set it up so each product I can input the total inventory, but I need to specify and track inventory per size of the product.  Hopefully this makes sense.  Seems like there were some plugins that did this for older versions of Virtuemart but can't find any for the latest.  Then there is talk about having to set up parent and child products, but I am not having any luck with that.  Can anyone help and tell me what steps i need to do to make this happen.  I right now have my 8 products set up as parents.  And each product has a drop down box with sizes x-small - xx-large.  But like i said, i can't set inventory for each size... just the the total inventory for the shirt.  Ideally, when the last shirt of a size sells, i want that size option to not show up as an option for the customer to order.  Thank you again for any help... greatly appreciated.