A question which comes on the Symantec Connect forums from time to time is whether Enterprise Vault has an evaluation (eval) mode. The answer is that it doesn't, but, the correct/better way is to request a trial key from Symantec or from a Symantec reseller.
At first glance that might seem a bit of a harsh way to go about introducing the product, but it's actually very good. Enterprise Vault, after all, does have many, many different operations, configuration capabilities and requirements. It's fairly easy to stand up a machine quickly to archive some items from a few mailboxes, but when you start to dig in to the details of FSA archiving, journaling, and policy management, never mind storage, and indexing, it can get quite complicated. So you really need some help, exactly what Symantec, and resellers can offer.