I’m like receiving podcasts/netcasts from the web, but in Ubuntu they do not play with the standard installation. This isn’t by accident nor is it an oversight, but is due to licensing and legalities. There are tons of Ubuntu Linux users, though, that have gotten them to work. There are a number of ways to do this, but the easiest way is to install Automatix2.
This topic is well covered in the Edgy Wiki: How to install Automatix2
The audio codecs are pretty straight forward to install with Automatix, but the DVD and other codecs are a little dicey with regards to legality so I’ll just leave them alone and will choose not to install them.