I am looking for a biling script, that automatically deducts from my customers monthly, and where I can keep track of invoices and stuff like that. Any suggestions...

Hi,

There are many options around:
http://www.rodopi.com/
http://www.ubersmith.com/ (see bottom of page)
http://webhostingbilling.com/
http://www.dreamcost.com/
http://www.modernbill.com/

hope these can help.
:)