How do I change the Store contact info?
You can edit the store contact info at Components > VirtueMart > Store > Edit Store.

"Recommend this product to a friend" feature sends an incomplete link to the item recommended
This feature does not work properly if SEF is enabled. SEF is the system that makes Joomla site links more search engine friendly. See this VirtueMart post for more info. You can turn off "Recommend this product to a friend" in VirtueMart > Configuration.