Are those screen printed or iron on?

Unfortunately, they are just iron-ons. Someone has made several designs and posted them on a firefly site. His site is...
http://home.comcast.net/~hellskitten/Firefly/ffmain.html
Under the Picture heading, click on Jayne shirts.
We have made more of these shirts and may end up posting more of the pictures.

What nice shirts. HER site, by the way, not "his."

I'll be adding more graphics based on newer designs from the movie and as well as some improvements to the current graphics. I was thinking about setting up one of those wacky online shops that makes shirts for you, but I wasn't sure if anyone would want to buy from them...? I also have a friend who does screen printing, but again, not sure of the outside interest.

Dude, I would SO buy a screen-printed shirt.

That URL for HellsKitten's site doesn't seem to work...?

The site link isn't working....and ooh, I would buy shirts, too. But in different colors! White gets too dirty when you're out cruisin' the 'verse. ;)

Hell's Kitten,
Sorry, didn't mean to be sexist by referring to your site as his. Loved your designs. My wife and I made shirts out of every one of them. In fact, we came up with one of our own. My wife wanted a shirt to match my soldier one, so she found the Chinese character for girl and made it look just like the soldier character. Now, she has a soldier girl shirt. If you are interested, we would be happy to send you the design and let you post it on your site.
Anyone who wants to see the shirt, and the others we made from Hell's Kitten's designs, you can go to my wife's site at.
http://www.angelfire.com/emo/selene/jayne
You may have to copy and paste this URL. I do not know how to make a hyperlink on these posts.
We also made a shirt from a design of the Serenity crew drawn South Park style.

Still can't find a shirt that is the exact color of the one Jayne had the Fighting Elves logo on.

Okay, sorry, but my site's temporarily down cuz of traffic. I'm gonna re-vamp it and put pictures of the actual t-shirts (including the right colored ones) I've made. I'll check into the costs of silk-screening / screen-printing / whatever you wanna call it. Right now, I can screen-print Blue Sun shirts by myself at virtually no cost. I can also print directly to a fabric iron-on instead of the crummy ones that peel and wear... I guess I should have started a thread on this instead of commenting on your pictures. Heh. Ooops.

if you have an ink jet printer and the transfer paper stuff, will that work? Or do you need a special printer?

What's a screen print?

I certainly am a huge fan of The Fountainhead and all of Ayn Rand's work. I'm glad someone caught the reference.
Ink jet printers work just fine. That's what we used.