So anyone who watches even a single episode of Scooby Doo (since they all pretty much have the same plot) knows very well that the only member of Mystery, Inc. to actually solve mysteries is Velma.
There's a different sweater and also different shoes. The bottom sweater is more "cartoon" accurate, but I love both of them. Really, I think getting Velma right is more about colors, the haircut, and those unforgettable square glasses!
One at a time, search for the following online (or at your local store):
Orange turtleneck sweater
Red pleated skirt
Orange knee-high socks
Red Mary Jane shoes
Square glasses frames
Brown page boy wig
Yes, I cheated again, but I think it's only fair to have some options for people who can't or are disinclined to sew!