This is from another guide:
Surf Idol Locations Guide
1) In front of the first sign.
2) After the 2nd gate, behind it.
3) Just before the 4th gate, in fron of it before you go through.
4) Through the 6th gate.
5) Through the 8th gate.
6) At the end of the slide after the big cave on the right after gate 7.
7) Just before the finish line to the right.
1) Just before gate 3, to the left of the ice rocks.
2) After the 6th gate. Jump on the ramp and it will be in fron of it.
3) A little bit after gat 7, before the multiplyer.
4) You have to go up the big ramp before the big cave.
5) After gat 8, it will be after the jump.
6) Just before gate 9.
7) On the ramp before gate 10.
Pen Gu South 1
1) After the first ramp.
2) Under gate 2.
3) On the right side in the cave.
4) Under the grind ramp after gate 4.
5) Under the big ramp before the big statue.
6) Under the big statue.
7) After gate 8, to the right of the ramp with the star.
Pen Gu South 2
1) After the 4th gate to the right.
2) After the 5th gate.
3) Along the grid ramp after gat 5.
4) At the bottom of the big ramp.
5) After the big ramp, there will be a small ramp, it's to the right of it, you must not go on the ramp in order to get it.
6) Behind the breakable wood just before gate 9.
7) Take the ramp on the right after gate 9.
Pen Gu South 3
1) To the left of the first ramp.
2) In the middle of the rocks after gate 5.
3) Just before gate 6.
4) After gate 10.
5) After gate 11.
6) Just before the finish line.
Pen Gu South 4
1) Under get 4 to the left.
2) Just before gate 10, you have to go under the small cave.
3) On the right ramp going to gate 12.
4) On top of the big ramp after the wave twirl.
5) Shortly after the big ramp you will surf around some stones it's near the end of them.
6) Under the 2nd big ramp before the finish, go under the ramp and break the wood.
1) Right after gate 1.
2) After gate 2, next to the pink shell.
3) Just before gate 5.
4) After gate 5, to the right.
5) Just before gate 8 to the left, take the ramp on the left.
6) After gate 9.
1) In the alcove after gate 1.
2) behind the breakable wood just before gate 5.
3) At the end of the ramp of gate 6, this is right after the wave so keep to the left.
4) After gate 8, just before the wave starts.
5) On the end of the ramp to the left of gate 9 right after wave #2.
6) On the right ramp before the finish line.
Pen Gu North 1
1) Right before the spikes.
2) After the ramp after gate 5.
3) In the middle of the spikes by gate 6, under the bridge.
4) Under gate 7.
5) Just before the finish.
Pen Gu North 2
1) Right after gate 2.
2) To the right of gate 4, in the alcove.
3) After gate 5, in the middle of the alcoves witht he breakable gates.
4) On the long ramp before gate 9.
5) In the alcove before the ramp before the finish line.
Pen Gu North 3
1) Behind the nreakable object to the left of gate 1.
2) Near the end of the wave on the right.
3) After the spikes you will see a long grind path, it's on it.
4) To the left of gate 7.
5) After gate 10, on the left of the long grind path before the finish.
1) To the left of the first big rock in the beginning.
2) Near the end of the wave to the right.
3) Shortly after the wave, between 2 stones.
4) Shortly after #3, to the right of the pink mask.
5) Right after wave #2 is finished, between 2 rocks.
6) Under the bridge shortly after #5.
7) Under the end bridge next to the green mask.
8) To the left before the green mask after wave #3.
9) After you see the pink mask shortly after #8, keep to the right.
10) By the stones before the finish.
1) Right before the breakable object, to the left of a large rock.
2) After the first long ramp there will be another one shortly after, it's on the left on it.
3) Shortly before the big rock crashes, to the left of the 2 ramps.
4) Shortly after the 2 small rocks crash.
5) On the right of the rock before the finish.
Leaf Sliding 1
1) Shortly after the 3 hour glasses.
2) On the right after the curve to the left with the hour glasses.
3) After the first blue path on the right.
4) Take the right at the fork road.
5) On the left near the waterfall.
6) In the middle of the waterfall which you go under, this is a different waterfall from #5.
Leaf Sliding 2
1) On the right after you exit the tunnel and see the blue crystals.
2) After the hour glasses on the left.
3) Just before the fork road on the left.
4) Take the left at the fork road and fall down.
5) To the left by the lava.
6) After you make the jump from the ramp in the middle of the lava.
Leaf Sliding 3
1) After the hour glasse on the left.
2) Take the left at the fork road.
3) Take the right when you jump, it will be behind a crystal on the left.
4) This one you can only get by playing this level twice, same as #3 but take the left instead of the right,
5) At the jump before the end.
6) Same as #5, but you have to take the left when jumping where #3 is, and stick to that road and you must not fall off.
Once you have collected all 100 *BING* Acheivement Unlocked