How to create an alert rule

hi…

plz help me to create an aleart rule for minimum stock of item…issue is that…

Item name - ABC

Onhand stock - 120

minimum stock- 50

if we pick the item with 71 quantity…then an aleart should be appear for minimum stock value.
same in mail alert.

please help me.

It might help you.

http://dynamicsuser.net/forums/t/50804.aspx