We use Vonage at the office and love the service and savings this VoIP (Voice over Internet Protocol) company provides.
If you're already paying for broadband, high speed internet access, then you're good to go and can sign up for Vonage's services. On their website they have a page explaining what Vonage is. It is, basically, "an all-inclusive phone service that can replace your current phone company." You buy a phone adapter that allows you to "connect your telephone to your high-speed internet connection." It's a one-time expense and you can buy it from Vonage itself. We bought ours at Sam's Club for $39.88.
We cancelled our Qwest business line altogether and now use Vonage to make unlimited local/long distance calls. We kept our old business number so nothing but the amount of money we spend every month has changed. We used to pay over $100/month, every month, for our business line because we use it quite a bit...now we pay $49.99/month and have unlimited long distance calling anywhere in the US, Canada and Puerto Rico.
Vonage has several calling plans you can sign up for. If the line you're setting up with Vonage is just a regular personal line, not a business line, then you can sign up for their basic plan.
Let us know how it works out for you if you decide to sign up with Vonage.