I had a few moments this evening and a desire to tweak, so I added a shortcut to the Petopia Pet Database that makes it easier to find pets with known skills. Now, when you are using the Pet Database, you can set Known Skills to “Any”. This will show you creatures that know any skill at all when they are tamed.
This is particularly useful when combined with a zone — for instance, you can find any pets in Darkshore that know a skill already so you can see what your young night elf hunter can learn there. Alternatively, if you just hit level 32, you might see what skills are available on level 32 pets.