Dear Webmaster,

I would like to inform you of an interesting opportunity for your website:
www.xxx.com
I am looking for reputable web properties to support us in promoting our clients' websites, and I would be more than happy to send you more information about our proposal.
If you are interested, please let me know and I will send you more details.

I look forward to hearing from you.

Best Regards,
Sean Greenberg
Advertising Consultant
Business Development Department