I'm no expert on this but if you use your favorite WEB Search Engine and search for skunks and castor you'll find LOTS of hits on the subject. Your search needs to include BOTH words (like skunks AND castor). Castor is what you want because there's a recipe that calls for Castor Oil in it.
BUT, if you can't find someone to help you with this, go to Understanding Skunks and read the entire page. In order to rid them from your 'area', you need to know how they live, breath, eat, sleep, and more.