The speciation examples I have read about don't seem compelling: two sets of creatures originally from the same population...after geographic separation for a period of time...their descendants can't produce offspring when reintroduced. Since the definition of different species is "can't reproduce" then this is speciation.
However, in my non-expert opinion, this seems a stretch to extrapolate a mechanism that results in inability to reproduce to account for the multitudes of the worlds species
A more compelling example would be a some obvious change along one of the dramatic evolution paths
It seems to me that in all recorded history, given the amount of trial and error that would be required to randomly produce complex structures found in nature (eye, wings, organs, metamorphosis, etc) mankind would have observed some changes, even though it's "only" been several thousand years
Evolution isn't random. Try to use references other than creationist crapsites so you will learn real stuff instead of made up nonsense.