Thank you! These were among my first attempts at ever carving stamps. My very first attempt was not even worth posting. They are all carved into a soft rubbery material called SpeedyCut by SpeedBall. I bought it in large sheets at a local art supply store and cut it to make smaller stamps. The tree branch is the only one that is an entire sheet of SpeedyCut and is a lot bigger than it might look.
The owl was cut with only an Xacto knife, but I eventually went out and bought myself some woodcutting tools to get that neat rough Bread and Puppet-y woodblock look. I got some books about carving out of the library, but for the most part I just winged it - all with my own designs (I looked at pictures online to get the basic shapes right). I used regular ink pads that I bought at a stationery store. I tried brushing on paint to see how I liked it...and I didn't.
I hadn't thought about making cards or anything with them, but I'll keep you posted if I do anything with them. The strawberry is my signature stamp for letterboxing, which is what started it all, and then I had just hoped I could frame a few prints of other images to hang on my walls.
And if this gives you a better idea of the material, here's a picture of the actual stamps:
Thank you for all your nice comments!