We need to auto-call people and give them various brief status reports via telephone.
We would create a spreadsheet numerous times during the day. Each time it saved to our computer, our computer would read it and automatically dial the people on the spreadsheet. The program would compare the before and after spreadsheets and call when the status changed. For example, column A has their phone number and column B their status "needinfo". The computer would see the word "needinfo" and access that voice file we would recored with our telephone. The computer would call that phone number and play the "needinfo" message. In turn, it would call all the people in the file where the status changed, and there was a voice file it could play.
We are open to your recommendations, but would prefer to use open source such as Asterisk.