The closest thing I could find was the Pixie in the Complete Book of Humanoids. To compensate for the pixie's abilities, it takes twice as much experience points for a pixie to gain levels. They also could only have a maximum strength of 14, a constitution of 16, and a wisdom of 16. They can only be fighterss and thieves.
Maybe something along those lines could work.
The Tomb of Horrors for 3.5 has the Quickling stated up with a level adjustment of +4.