I'd be happy to help you and explain how I did the Obama illo. It's not as hard as you think.
I actually got the idea from watching a CNN promo on the 100 days of Obama about two months ago, and I thought that would be cool. I thought if we ever did a story, I would give it a shot.
First thing was to find the right photo. I knew it had to be a tight crop and easily recognizable. With Obama, it's pretty easy because he is photographed so much.
Secondly, I schetched out on Quark using our paper's most bold san sarif font to see how the numbers would line up to the photo I selected. The font I used was "Stainless Black" I realized in that process that I couldn't put any spaces between the numbers or it would have looked choppy. Also, I had to play with the numbers so they would be as modular as possible.
Once I figured out the number layout, I typed black numbers on a white background in photoshop like I did in quark. That whole number pattern became one layer. Then I did the following:
I highlighted the layer, which was all the black numbers.
Flattened the image.
Inversed the highlight so that the white background was now highlighted,
I copied that highlighted white and pasted it on the image of Obama.
By doing this, I basically created a white layer that had number "holes" cut into it.
I adjusted the numbers a little bit so Obama's eyes, mouth and ears were in the image. Once I did that, I highlighted the white again, flatted that image and reverse highlighted so that now the little number holes that had Obama's image were highlighted. I then copy and pasted that layer onto a new photoshop document.
I realized that the image wasn't "popping out" enough, so I decided to give the numbers a shadow layer. This step is really easy,
Duplicate the layer on your new photoshop document.
Highlight that new layer and fill it gray.
Blur that gray layer.
Put the gray layer behind the orginal Obama numbers layer and move it 2 points right and two points down.
Flatten it and you're done.
Jeeze, I hope that wasn't too confusing.
If you have anymore questions, please feel free to ask.