Hi:
Assuming you are in the USA, it's relatively easy to do this with an OBi, a Google Voice account with a Google Voice phone number, and a Callcentric account with a free inbound number (NY State DID number).
Google Voice has a Chrome browser extension that will enable click-to-call functionality. You'll select your Callcentric number as the call-with target, and then Google Voice will call you on that Callcentric number, and finally, it will call your desired party's number and bridge the calls together.
You will first set up Google Voice on one of the OBi's four Service Provider slots (SP1--SP4), and then set up the Callcentric number on another slot, and add the Callcentric number as a forwarding phone number to your Google Voice settings.