I found two interesting sites:  www.Greek123.tv sells textbooks etc. for learning Greek, but as a sample has some of its chapter dialogues in short video clips.  A few of the videos are intermediate, most are very simple, but they are all interesting for practice and some have subtitles.  Unfortunately they don't seem to be in order.  I found them on Youtube as well though by searching "greek123" and could pick which one I wanted to watch.
I also found this site: http://www.gutenberg.org/browse/languages/el which has some old books (some may be in Katharevousa--they're so old it's hard to tell) in Greek to download for free (as well as many in other languages as well).  I'm not sure if it's legal to download it in a European country, but it says it is in the U.S.A.
Renee