go here: http://www.wiziwig.tv/competition.php?part=sports&discipline=football scroll down to the where the arsenal game is. Click on it, and it will give you lots of links. The "Flash" links will be to internet streaming sites. The other ones like "sopcast" require you to have some software, but it can all be downloaded from that site's download section if you want.
Wiziwig generally has the most comprehensive set of links, and if you want a quality (HD) stream there's usually a few of those for Sopcast. Well worth the install.