The site is open to any registered Apple developer and it's free to become a registered Apple developer--you don't actually have to be, you know, a real actual coding or programming developer. Just sign up for an account here.
Apple has a handy best practices page to help you submit the best bug report possible. (Hat tip to our own Laurie for this great link!)
And here are a few more helpful contact points:
AppleCare Extended Service and Support (800) 275-2273
AppleCare Support - 90 Day Warranty (800) 275-2273
AppleCare Support - Legacy (800) 767-2775
AppleCare Support - Education (800) 800-2775
Apple Store (Consumer) (800) MY-APPLE (800-692-7753)
Apple Store (Education - Individuals) (800) 780-5009
Apple Store (Education - Schools) (800) 800-2775
Canada AppleCare Extended Service and Support (800) 263-3394
Canada AppleCare Support - Education (800) 800-2775
Canada Apple Store (Consumer) (800) MY-APPLE (800-692-7753)
How to get a human faster? Press Zero three times. If a virtual rep answers, say "Operator".