I removed the skills from my skill bar to move them to page 2 for easier use in combat, however, I can't find them in the skills tab, I've looked in all the talents, and it's nowhere to be found. Is this a known bug, or am I just blind?
Deleting hotbar.json (~\AppData\LocalLow\LoE\Legends of Equestria\hotbar.json) should reset it, meaning that all the symbols are there like they were at the beginning. (Replace ~ with the path to your user folder)
You will have to close and restart the game for it to have an effect. I don't know if it is possible to move Ground Pound and Bubble Barrage to a different bar, since, as you said, they are not in the skills book. But that should restore it.
When you delete hotbar.json, the game will create the file again with default settings.
I used it when I lost my teleportation spell.
Alternatively, they should be in your quest log on the 'other' section of your skills (index) page. Upon the first room and instance you spawn in, teleportation, ground pound and bubble barrage should all be there. After you swap room instances or move to another area, say, Cantermore to Ponydale, they disappear. It's a long time bug.
Deleting your hotbar.json file isn't really ideal unless you're having no luck getting them to show up on your index page. It means having to set up all your skills and emotes again which can be a bit of a pain, haha