I'm glad that you asked where to get porcupine quills! 

Actually they are easy to find. They are used a lot in Native American
arts.
The first site below is just a Google search.
The last site listed below tells you why dogs and porcupines do not get
along.
The main differences between hedgehog and porcupine quills is that
hedgehog quills are relative smooth and easy to use. Porcupine quills on
the other hand are much larger, have barbs and can be really difficult
to remove when embedded in skin. 
Leave those critters alone!!!.
Barry


http://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=porcupine+quills&
btnG=Google+Search

http://www.rzu2u.com/quillsale.htm

http://www.farmandfield.net/quill.html

http://www.naturallist.com/quills.htm

http://www.petsmart.com/pet_library/care_guide/ch3/porcupine_quills.shtm
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