Phone companies develop Internet plan
RingtoNumber seems like a cost-effective service; heck, the basic service is free. For that, you get a non-local number with a "shortcode" attached, that is keyed to your number.
[General] Cheap DID recommendations - dslreports.com
I noticed just now when I tried to log into my SipNumber account, it forced me to a RingToNumber control panel. That control panel allows forwarding only to a PSTN number, not a ...
Free DID Numbers, Free Voip Calls, & more Voip Info - Voxalot / SIP ...
http://www.ringtonumber.com This service is a shared number, with an extension for each user. They claim that now though you can forward for free to your own phone number.