Didn't Angie recently blog about this - or did I just dream it.
I struggle finding pencil skirts because I'm petite and have not much of a butt. The first problem is that the zipper is usually too long (even with petite sizing) so it ends up bunching funny. Then there's the gut factor - but that not as bad as the butt/zipper issue.
I have one pencil skirt from H&M this past summer that fits like a dream.(*) That's it. No luck elsewhere, but I should admit I'm not trying all that hard to find one, since I rarely wear skirts in the fall/winter months.
(*) Footnote added: so I know it's not my body that is the problem - it's the darn fit of the skirt.