How can I pay less and talk more ?

Best way, in our opinion, would be by using an open source ( free) application named Asterisk
as it will allow you not only to save money, but to have lots of features added such as voicemail by email, Call waiting, Call display, Call parking, "follow-me" extension, customized rings ... etc.
You will need to install it on a Unix server ( or a virtual one ) and configure it
You will also need to purchase a DID ( Direct Inward Dialng ) from a VoIP provider
( this is simply a phone number like 416 555-5555).