Hi [COMPANY NAME]!
Was I ever DELIGHTED to discover your website while looking for [PRODUCT].
I wanted to get in touch with you to see if your company might be interested in a unique marketing collaboration. My name is Brooke McLay and I am the owner of the online food & lifestyle website http://www.tongue-n-cheeky.com/. My site holds a Google ranking of x and recieves over xx,xxx visitors per month. [ETC, ETC].
On [DATE], I will be posting on [DETAILED INFORMATION ON UPCOMING POST]. That day, I would also like to offer a giveaway to site visitors. I was wondering if your company might be interested in donating a prize for the event. [ETC, ETC].
To thank you for your giveaway donation, I would like to offer you a month of free advertising for your company through a square sidebar button placed on my site.
I look forward to hearing from you and hope you're up for it! I believe the collaboration between your site and mine will prove very worthwhile for your company.
Thank you so much!
Brooke McLay, http://www.tongue-n-cheeky.com