Call Management Software

Who knows how much does Call Management Software cost? I want to reduce communication costs. For this I need a proven service, who can you recommend?
Hi, I just recently decided to try using this tool. Many entrepreneurs use call tracking in order to track incoming calls. Now I am testing a trial version of the starter package here Has anybody heard about this service before? Prices are low, hoping to see results. Using the free version too, maybe this service could help.