voip click to call in php auto dial api intergtation

hi, Im not sure how to best explain this but this is what i am looking to do We are a small telesales operation and are currenly useing a voip sysytem. our sales team is split in to two halfs 1 prepares the quotes where the leads are provided by third party websites ,the other half phone these quotes up at present the quote are preapred by 1 team and emailed over in excell format for the sales team to phone the customer up. my voip provider has an api which could automate this the code is already written it just need a lttle jiggery pokery and setting up. What i want to happen if for the spread sheet to provide the data for the chosen extension to auotmatically dial for ,the agents. The agents phone need to ring first and the customer be identified by their unique refrence number. any questions please ask