Yahoo! takes takes things easy when it comes to sending in DMCA take down complaints. Their form is one small page of the basic information required. Research is being done to see if there is another takedown form required for the Japanese service, as there have been many misguided attempts through this form, to no avail. They seem to work under different bodies. So, don’t use this site for claims in the Pacific Rim (especially Yahoo! Japan). The takedown form can be found here!
The only real thing to be aware of is the selection of claim. It would be assumed that the reason for the copyright claim, like the Google site, is because you found an image in their search that is not to your liking, as it infringes on your rights. So, simply select “Image Search”