Can somebody please tell me where all the secret yoshis are besides the..

The black and the white yoshis are the ONLY secret yoshis in the game.

Black Yoshi: Page 2, Level 2. - After you go through the first part of the level (Bone dragons), go to the bottom of the next screen (After you go into the jar). In order to do this, you will need to break some blocks, and, by all means, feel free to do so. Once you get to the bottom of the screen (You have to be under the little platforms), eat the Tulip, and go up. Pop the bubble up there and, Voila!, you have the Black yoshi. White Yoshi: Page 3, Level 2.
- Once you get to the leaf surfing part, don't get on the leaf. Just walk straight off of the platform. Go left ( *<---* ) and go past the egg block. Pop the bubble and, Voila!, you have the White yoshi.

Purple Yoshi: Any level
- Collect all of the coins on any one level.


*Just as a hint, if you want to know, If you want to keep all of the hidden yoshis, beat the last page with your newly unlocked yoshi (Entire page, not waiting until another one dies). Then you can start the game over with the unlocked yoshis and not go through the hassle of getting them again.
And, by a strange coincedence, you can see the epilogue with the yoshis you unlocked. YAY!

You get gold yoshi by getting black and white yoshi and get in the top 5 in all levels in trial mode.