How To Write A Community Service Volunteer Letter . Tell the number of hours the volunteer served. I am writing in response to your advertisement regarding volunteers for your community center. Community Service Letterhead Sample free printable letterhead from www.freeprintableletterhead.net A community service letter is a document which verifies that some kind of community service was provided by an individual. The parts of a motivation letter include. If you are emailing the letter to the hiring party, you may need to print out a copy of the letter, sign it with.