There are a lot of streaming sites on the web that offers videos in divx, mp4 and mostly flv. Try searching at Ant. They have a directory of video streaming sites plus they offer a free downloader that works with any sites.
www.internetarchives.org has many classic and even color movies that can be downloaded with out any charge. These movies are in the public domain. The movies that are not in divx format can be converted by using a free converter like any video converter and the free xvid codec. Xvid is an open source compatable alternative to divx. Search the moving images section at the archives to find movies by category. There are also groups on the web that trade and distro movies in divx format. Caution should be used when trading online since much of this material is copyrighted and not legal to exchange in many countries and often viruses tag along on the discs exchanged. It is also possible to lose your identity on some of these groups since you must give them your name and address for mailing.