How to write a good query/offer on a house?

[Andy Thoman]

I was out driving today, and I was just keeping my eyes open to be driving for dollars at the same time.

I saw a house that look abandoned, so when I got home I looked it up. Sure enough, the owner is not from here. So I would like to invest this opportunity further, but I've never done something like this. I have the owners address, phone number, and email from digging I did online.

Here are my main questions:
What is the appropriate way to contact them?
Should I make an loose contingent offer, then go see the property and make a better offer? Or should I just say I'm interested, go see it - then make an offer?
What information should I be checking out for Due Diligence in the meantime?
Are there any good articles on writing a good letter of interest /  phonecall script? Or does anyone know of an example or sample I can look at?
What else am I forgetting that I should keep in mind?