Okay, I got nothin.....I've never written a letter like this, and I don't know what to say. I don't want to put too much in the letter or too little, but right now I've got about 4 sentences....LOL! Here it is:
  
RE: Lot 292
Dear Sir,
  We are writing you to inquire about purchasing the lot neighboring our property immediately to the north, Mullendike Lot 292, of which we were told you are the owner. We would like to buy this property as-is. If you are willing to negotiate a sale of this property or if you are not interested in selling it please contact us at the phone number listed above at your earliest convenience. Thank you, and God bless!