Out of time for what? Is this about you learning or about an emergency at work, or are we filling in for an interview?
For a great start on DMVs, I'd recommend Tim Ford & Louis Davidson's book, Performance Tuning With Dynamic Management Views
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning