I had trouble finding it as well! It's found in Nimbasa City in the house above and to the left of the pokemon center. The Ace Trainer will give you it. I hope this helps!
the hm move strength is found in the cave Rusturf tunnel
You get HM Waterfall at the end of Route 18 on the strip of grass in Pokemon Black.
No, you cannot get the HM Rock Climb in Pokemon Black or White.
You get strength in a house in Nimbasa city, right north for the battle institute and Pokemon center.
Pokemon Black and White don't have HM Whirlpool.
It's not an HM in Black and White.
You cannot get the TM/HM Whirlpool in Pokemon Black or White.
Rock Smash isn't an HM in this game.
yes
HM Waterfall can be found on Route 18 in Pokemon Black and White.
At nimbasa, in the house northwest of the Pokemon center.
hm im not sure