Below are some links to assist with DMCA Takedown Notices. Many sites have forms to fill out that assist these kind of requests, otherwise you may use a template and send it to the site administration via email.
Re: Copyright Infringement
Dear [Copyright Agent Name / Contact of site where infringing content is]
I am the copyright owner of the [type of content] being infringed at:
x[List of URLs where infringing content can be found]
A copy of the [type of content] being infringed is included to assist with its removal from the infringing websites and can also be found here:
xxxxxxxxxx[List of URLs where ORIGINAL and approved content can be found]
This letter is official notification under the provisions of Section 512(c) of the Digital Millennium Copyright Act (DMCA) to effect removal of the above-reported infringements. I request that you immediately issue a cancellation message as specified in RFC 1036 for the specified postings and prevent the infringer, who is identified by its web address, from posting the infringing material to your servers in the future.
Please be advised that the law requires you, as a service provider, to remove or disable access to the infringing materials upon receiving this notice. Under US law, a service provider, such as yourself, enjoys immunity from a copyright lawsuit provided that you act with deliberate speed to investigate and rectify ongoing copyright infringement. If service providers do not investigate and remove or disable the infringing material this immunity is lost. Therefore, in order for you to remain immune from a copyright infringement action you will need to investigate and ultimately remove or otherwise disable the infringing material from your services will all due speed.
I am providing this notice in good faith and with the reasonable belief that my rights as the copyright owner are being infringed. Under penalty of perjury I certify that the information contained in the notification is both true and accurate and I am the copyright holder.
Please send me at the address below a prompt response indicating the actions you have taken to resolve this matter.
Sincerely,
[Your Name]
[Your Address + Your Phone]
[Your email]