First if your looking for a good pixel font then download this one: pixelfont. This font works best at size 6 and capslock ON. Sample of the font to the right.

Open up the image you want to use and then take the text tool (Name: pixelfont | Size: 6 | Create As: Floating) and type text with capslock ON. I'm typing "Imusion is the Best" with the fill color being "#2E2E2E" and no stroke color.

With the selection of the text still active (the little "ants" should be moving around the text) now go to Effects--> 3D Effects--> Drop Shadow. Use these options below and you can change the Color to your preference. It is best to use a dark color if you used light colored text and vice versa.