It's really easy, and it actually worked. The main post is on adding the same image before every post title, but scroll down to the Update, and you'll see how to add different images.
PS--If your image is pressing too close to the title, you can add some breathing room by entering a few spaces (just hit the spacebar key--no complicated coding) between the HTML code given and your title. I added two.
So what do you think of my little date icon? I think it adds a little personality. :)
UPDATE: I found out a different and easier way to customize the posting date. I will write a post about it soon. But so you know what I was talking about in this post, this is how I was doing it:
I do like how this little icon looks, but now I don't have to create a new image for each post.