I am an ex-evolutionist who is now a 6 day creationist. Although I think that there are many excellent reasons to reject evolution, perhaps the most effective in convincing people who are not totally committed one way or the other is in the matter of living fossils; that is, those fossils which have living offspring which reveal little or no change despite the supposed millions of yrs between them.
Most of the photo illustrations I will give come from Dr. Carl Werner who in his work Living Fossils: Evolution, the Great Experiment reveals how he made a world tour of various museums and saw first hand the many fossils that still have living descendants and how he obtained candid interviews from the curators and/or heads of those museums. Many of the comments he garnished in his tour brought out statements that fly in the face of the status quo of accidentalist thought.
I have hundreds of examples but I begin with this:
The oldest fossil bat on record, dated at 50 million yrs old. (Note: I do not accept the time frame of evolutionist conclusions).
Compared with the skeleton of a modern bat:
Notice that the shape, contour, symmetry, and number of phalanges and the head are all the same. So why no evolutionary change in 50 million yrs? The most damaging thing to evolution about this is that there are no transitionals either before or after this bat. Other species have been found of course, but none reveal any change either from another organism or a change into something else.