All TMs and Where to Find Them – Pokemon Sun and Moon
TM21: Frustration – Head to the Malasada Shop in Malie City (Ula’ula Island) and talk to the Oranguru.
TM22: Solar Beam – Sold in the Seafolk Village Pokemon Center on Poni Island for 10,000 Poke Dollars.
TM23: Smack Down – Sold in the Malie City Pokemon Center on Ula’ula Island for 10,000 Poke Dollars.
TM24: Thunderbolt – Found in Poni Planes on Poni Island. Once you enter the area, head left and make your way up, then head all the way to the left and go down to find this one on a rock.
TM25: Thunder – Sold in the Seafolk Village Pokemon Center on Poni Island for 30,000 Poke Dollars.
TM26: Earthquake – Found in Resolution Cave on Poni Island by using Tauros. You will need to first become champion to access this area from the north of Ancient Poni Path, so this is an endgame TM.
TM27: Return – Given to you by the Oranguru in the Malasada Shop in Malie City (Ula’ula Island).
TM28: Leech Life – Head all the way east on Route 9 in the lower right hand corner of Akala Island to find this TM in a corner near the water.
TM29: Psychic – This is a gift from Wicke when you leave Aether Paradise for the first time.
TM30: Shadow Ball – Found on Route 14 on Ula’ula Island. Head west near the water and you’ll find it at the base of where there looks to have once been a tower (It’s a circle with bent steel around it).