Absentee Owner Letter

I have a few absentee home owners of vacant properties that I need to contact. Seeing as how I’m new at this, I need a little help composing a letter to them letting them know that I’m interested in the property. Any suggestions? I’ve also heard of people doing follow-up post cards. If I sent those after I sent out letters what would I say, “hey remember that letter I sent a few weeks ago?”. I just need a few suggestions on wording. I don’t them to throw my letter or post card in the trash without reading it!

Thanks,
Tami