You posted this question on the general DIY forum, where it won't necessarily be seen by the original poster of the project to which you are referring. Can you try to find the relevant post and ask your question in the Questions section there, so they can see it and respond?
You should be able to find them in any craft store like Hobby Lobby, Michael's and A. C. Moore. I've also seen them in Walmart, Target and even Dollar Tree. I'd suggest that you look online first to see what each store has to offer. You can also get them online at Amazon.com . If you want a specific transfer, as T R stated, you'll need to find the project and ask that Hometalk member where she got her stencil. Wishing you the best.
I've seen them on Amazon.
Evelyn: you can find them on amazon.
Evelyn....Craft stores should have, even fabric shops or dept.