theres a program called netlimiter that will monitor the bandwidth usage of any app
http://www.netlimiter.com/download.php the monitoring tool is free but the full version is not free
it monitors every program with a conection to the internet, it also monitors every ip address and which port each is using and how much bandwidth each is using it can also graph out bandwidth usage
if you have a linksys wrt54g v4 or older
or a wrt54gl
then you can install the ddwrt firmware which will give you many bandwidth monitoring tools as well as the ability to control how bandwidth is used and prioritized