If you use PNAC you can create a job that reads the list of switches. This happens with a SNMP protocol and you can read out the following things:
nothing -> data is read out and stored on the server
update -> * update inventory completes the Active Network Components
alert -> is only able for mac and emails an alert, when the mac on a port gets changed.
You can combine SNMP only with an email which sends the data and you are only able to choose the switches in groups witch a tag. This only works, if the switch has an IP address and a community string and it has to get assigned to a radius sever.