AsteriskBilling.com - General technical and billing information for VoIP operators using Asterisk PBX.
Below are a list of some of Asterisk Voip Billing applications:
AgileVoice - http://agilevoice.com/
Alepo - http://www.alepo.com/
Aradial - http://www.aradial.com/
AgileBill - http://www.agilebill.com/voipbilling
Astbill - http://astbill.com/
Astpp - http://www.astpp.org/
Freeside - http://www.sisd.com/freeside/
MCC - http://www.paskambink.lt/mcc/
Trabas - http://www.trabas.com/opensource/
Vanable - http://www.vanabel.com/