If you want to download videos from Yahoo, you only need the LyFOX.
The LyFOX application does the dirty work of locating each music videos unique MMS:// URL without having to navigate the Yahoo! Music site.
Download the app and run it.
In the main window, type the name of the artist you want.
You can go and on Yahoo's top list to view some top videos. For example in the top page, the first video is (right now) the Smack That from Akon.
So type Akon end press enter.
You will get the results.
Double click on any name and in the form below, you will see the link.
Click on the small C button left to form. Now open the flashget, and select new download. Paste the url. Your video will starting to download.