Have you try to download video from :

YouTube, Angry Alien, Blennus, Blip.tv, Break.com, Dailymotion, Double Agent, eVideoShare, Free Video Blog, Google Video, Grinvi, iFilm, Keiichi Anime Forever, Metacafe, MySpace, MySpace Video Code, Putfile, Totally Crap, vidiLife, vSocial, AnimeEpisodes.Net, Badjojo, Blastro, Bofunk, etc …

It is not a simple way to do… but it will be different if you try to use the tool below…

Search for MP3 Files or WMA Files on internet using normal search method caused thousand page result. How to search for MP3 Files Only or WMA Files Only ?

Google Gadgets are miniature objects made by Google users like you that offer cool and dynamic content that can be placed on any page on the web. They’re free and available for you to add to any webpage that you own, and can also be added to various Google properties (your iGoogle page, Google Desktop, Blogger, and Page Creator). Here are answers to some of the most common questions we anticipate you’ll have as you’re adding gadgets to your own webpage.

Source :

http://code.google.com/support/bin/answer.py?answer=57803&topic=10043