The code is: JUNEPERK it is case sensitive so be sure to make it all caps. I found that this website has a lot of good working coupon codes..
You have to purchase something $15 and up but it's great for a new light bulb like what I got from there!
http://www.retailmenot.com/view/petsmart.com (that is the link for more pet-smart codes, haven't tried all of them)
Hope I helped some people out!