Hi Karthik,
1. /SAPAPO/AMON_REORG helps to clear database alerts which are saved in system. Please note only data base alerts are saved in system and dynamic alerts are not saved in system - These are determined by system at runtime - so the name dynamic.
2. Please have a look at below two documents - Here Alert functionality along with configuration steps are explained nicely -
Hope it helps.
Regards,
Alok