I am far from being an expert but the little research I've done on the patent/copyright/trademark world seems to imply that for us crafty types copyrights are more appropriate. Patents are for inventions or processes, not designs. Although, if you have invented a useful and functional thing or a process for making such a thing maybe you do need a patent! The whole she-bang is spelled out here: US copyright office http://www.copyright.gov
and US Patent & Trademark office http://www.uspto.gov
Hope this helps!