I may be wrong, but I think it only comes with the non-free versions of SQL server.
What you may like to do, if you're serious about SQL is buy a copy of developer edition. It's only $50 or so, and has most of the features of enterprise, just with a development-only licence,
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
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