You guys can make your shirts at cafepress or zazzle.
If you want to sell them, I suggest cafepress over zazzle for many different reasons. I've designed shirts I sell on both, but I promise you it's not a whole lot of money, but I seem to do much better on cafepress than zazzle right now.
Also, if you do sell them, make sure you are using fonts that are free for commercial use. There's a bunch online, but it's not easy to find, but Larabie Fonts are free for commercial use (generally, but double check in case they changed things up). You can also find some dingbat fonts (all pics) that are free for commercial use as well.
I've tried very hard to come up with Asperger T-shirts, but I get a serious writer's block with it. Most of my shirts are military and mainly military Brat related.
Also, wrong planet is on cafepress. You should have a link to the wrongplanet online store right under your user stats to the right.