VMware recently extended the general support for vCenter Lab Manager to May 1, 2o14. Originally the product was supported till May 1, 2013.
I have not read information before on this renewed extension of support although the document is published in February 2013.
This means customers with a Support and Subscription agreement will have phone support and access to maintenance updates till May 1 ,2014.
Lab Manager itself cannot be purchased anymore. VMware vCloud Director is the product which now offers features like Lab Manager offered.