So, multiple questions in one.
First, I have a drawing of some Pokemon I want on a shirt ('m a nerd). I know that they’re a huge company and I don’t want to mess with their copyright laws, but I want to sell the shirt to some friends and perhaps online. It’s an original drawing.
Second, I want just one copy printed and here overnight (in time for the release of the games).
Am I asking for too much? I’ve never had any of my shirt designs printed…
THANKS SHIRT.WOOT PEEPS! 
Just realized the title can be misconstrued as an “I have advice for you” kind of thing. shrugs
Disclaimer… I am not a lawyer, but here’s my take:
First, as far as putting Pokemon on the shirt, I think you’re screwed. Custom shirt design places tend to have a disclaimer saying to not put copyrighted material on the shirt. Not to mention selling it to your friends could amount to selling a copyrighted item (something not allowed unless you make an agreement with the copyright owner, which usually involves paying them royalties… selling the shirts online could definitely get you in trouble!).
Perhaps you could get around this because it is a custom drawing, and just say it’s a drawing of an anonymous “imaginary creature” or something. Not sure.
Second, I think printing only one copy and shipping it overnight to you would be prohibitively expensive and not worth it. Custom shirt places tend to want orders of multiple shirts at once, and raise the prices for the fewer you order. So order them for you and your friends at the same time (and it will takes longer than overnight… again this is just my experience, but it can take some time for them to actually PRINT the shirts).
Thanks for the feedback! It’s totally just for a nerdy cause, so probably not worth the trouble with the copyright and cost. I guess my best bet would be to do an iron-on transfer and just distribute it to friends.