STATS_DATE()
It's a function, use it in conjunction with sys.indexes or sys.statistics.
Or, if you just want the details for one stats set, DBCC SHOW_STATISTICS will also show last update.
Bear in mind that stats that haven't been updated for a while are not necessarily a problem. It's only a problem if there have been lots of data changes in the interim.
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