I list following VOIP service providers, which I put into my research pool.
www.dialpad.com
www.teliax.com
www.freeworlddialup.com
www.sipbroker.com
www.ipkall.com
www.voiptalk.org
www.stanaphone.com
www.mutualphone.com
www.broadvoice.com
And also following service providers:
www.voipbuster.com
www.voipstunt.com
www.voipcheap.com
www.sipdiscount.com
www.sipgate.co.uk
Here is some information site for services and providers.
www.voipuser.org
www.voipcharge.com
