Fade to Transparent

Hello all! I am fairly comfortable using PSP for basic image tasks, and I understand image files. However, I am asking for help on how to fade an image to transparent at the edges. I am trying to re-create the effect seen in the below image.

Attachment 102675

What I have so far is the base image, a black rectangle with two white lines at the top and bottom. I am guessing that I need to add a new layer on top of this layer, but that is where I get completely lost... How can I take my image and fade the edges smoothly to 100% transparency? Or am I going about this the wrong way? I appreciate any help you can lend!

Attachment 102676