Just go to Facebook's Like Button page
It'll generate the code for you. You can use the iframe syntax it creates to keep it simple.
When entering information in their boxes, enter any URL into the top box. The code it gives you will look like:
<iframe src="http://www.facebook.com/plugins/like.php?href=YOUR_ENCODED_URL&layout=...... ></iframe>
Where it has your URL, if you decide to show the Like button for each post, you can place this iframe code in your theme's PostView.ascx, and replace YOUR_ENCODED_URL with:
This will put the absolute link of that particular post in there -- rather than a link that might just point to your blog's homepage.
If you test this on your local machine, the Like button will display, and you can click it, but you might see an Error because when clicking the Like button, Facebook tries to go to your page and it won't be able to access a page on your local computer.