First open the image you want, And click effects > then Artistic effects then halftone.<br>
<img src="http://www.neopremades.com/images/tutorials/PSPX/1.PNG"><BR>

Then Mess around with the settings you want, and click ok<br>

<img src="http://www.neopremades.com/images/tutorials/PSPX/2.PNG"><BR>

And your done, your image should have lines like this:<br>
<img src="http://www.neopremades.com/images/tutorials/PSPX/3.PNG"><BR>