IF you want to install Maven in Eclipse(Java EE) Indigo Then follow these Steps :
Eclipse -> Help -> Install New Software.
Type " http://download.eclipse.org/releases/indigo/ " & Hit Enter.
Expand " Collaboration " tag.
Select Maven plugin from there.
Click on next .
Accept the agreement & click finish.
After installing the maven it will ask for restarting the Eclipse,So restart the eclipse again to see the changes.