There are many places you can get "embossing tools" I'm sure, but two that I know of are Arrow Springs and Leonardo Lampwork. You aren't limited to using "lampwork" tools, you can use any brass tools that won't stick to the glass, like ceramic clay brass molds.
Arrow Springs Wave Press
Leonardo Lampwork Lollipop Press
It's pretty easy to use an embossing tool, I won't go picture by picture, but I'll explain it to you. Make a base bead. For my beads, I used a Zoozii bead press to make a lentil-shaped bead. When you are happy with the bead shape, heat one side of the bead. Make sure not to heat the bead too much or the bead will get out of shape. Place the bead on your torch-mounted marver (if you have one, if not, use your graphite marver) and press the tool into the heated side of the bead. This is trial-and-error - make sure you don't heat too much or press too hard. Take it out of the flame, and make sure you like your press. If you don't, heat the bead up and shape it again. When you're happy with the press, turn the bead over the repeat (if you want the design to be on both sides), making sure not to heat the bead too much or you'll lose the design on the first side!
Donna Millard is a bead artist who uses embossing tools to make amazing beads, and she embellishes them with patina. These beads are gorgeous!
Genea Crivello-Knable is another bead artist who uses embossing tools on her beads!
I hope you enjoyed this little tutorial/eye candy post! You can see that you can really add many elements to your lampwork beads to make them stand out!