Just wanted to say thanks to the original poster of the tutorial, and all those who added helpful tips along the way. I stencilled two t-shirts this week and was happy with how both came out. Pics of one are linked; the Daria design was borrowed from s t e n c i l r y. Just as an FYI, I took a couple of tips and combined with the original tutorial for the following method:
(1) printed design onto cardstock paper. glued another sheet to it to make it thicker. taped the whole thing up with clear packing tape. then cut out with exacto knife (the most tedious part of the whole process.) but you're left with a stencil you can use several times.
(2) piece of cardboard inside the shirt to prevent bleed through. stencil masking taped down.
(3) fabric paint! is only mildly more expensive, can be washed, and therefore no mixing with primer or ironing -blech! foam brush up-and-down - as recommended, was very simple. small paintbrush for touch ups and bridges when complete.