I'm wondering how people make stamped monogram cupcakes. The ones where the letter is actually just sunk or pressed into the fondant. Are people just using regular rubber stamps? Help!

Those look like Martha Stewart's - check out

http://www.marthastewartweddings.com/article/stacked-monogram-cupcakes

The description says rubber stamps were used.

A never-used-for-ink rubber stamp, thouroughly cleaned

I wonder if you could make a stamp with royal icing by doing a runout of the letter. Once its hard, stick it on a piece of gumpaste and press into the fondant.

to grrrl
Ilike to look around Michael's craft Store and i got to the scraptbook section, there I saw clears plastic embossers of all kinds
I bought some and practice on reg fondant and also 50/50 fondant&gumpaste , it worked! after that you get to choose anyu shape or size of cookie cutter.
to sweetooth... yes you can also do as you say, it also works.

Micheals sounds better, makes life easier

Well I was going to answer the question, but you all beat me to it...
to the site!

I love stamping on fondant and gum paste. I've done a lot of card making and decided I wanted the intricate details on cakes.

I stamp on 100% fondant, 100% gum paste, or 50/50. Make sure the medium is a little dry by rolling is and leaving it out for at least 30 seconds (depending on temp and humidity in your area). Dust your stamp with 50/50 powdered sugar/corn starch. Stamp straight down and with an even pressure.

You can stamp designs using edible inks. I use edible markers for small stamps and liquid colors for larger stamps. The markers dry out fast, so they don't work well for large areas. Don't use gel colors (with or without water) since they never completely dry.

I get a lot of stamps from Michaels and JoAnns. They have great coupons and lots of sales. Be sure to mark the stamps for food so you don't mix them up with regular stamps used with ink. A lot of times you can find a letter set on sale.

Hope this helps. Good luck.