The Properties window appears most often on the bottom of the screen in Dreamweaver (it differs in various versions).

Here, you can change where your type goes on a page by clicking on one of the little sets of lines on the top right-hand side of the box:

Other ways to position type or pictures on the page:

You can position your image by clicking on the "Align" box at the bottom right-hand side of the Properties box, or by giving pixel coordinates in V Space and H Space (Vertical, Horizontal).