That information is not stored anywhere. If you need that, you need triggers on the tables, a trace, CDC, change tracking or maybe SQL Audit, depending on exactly what you want.
You can use the index usage stats DMV to get the last change to an index since SQL was started, but it does not differentiate between insert, update or delete and the information does not persist across a service restart
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