You don't mention if you are in the U.S. or not, but if you are:
The free app (in the App Store) Talkatone allows you to use Google Chat. It's a matter of getting the app, signing in to Google, making one test call from your PC/Mac (to initiate Talkatone) and bang! You're done.
I use Talkatone for my voice calls here in the USA. Can't beat free...
Marilyn