That's too bad, accidents happen.
Your main options are A.) bring it to Apple, B.) bring it to an Apple authorized service center, C.) bring it to an unauthorized third-party repair shop, or D.) find the parts online and do the repair yourself. Note that the standard warranty will not cover damage caused by the user (you).*
Each option will have different costs associated with it. It's up to you to research the options and determine what falls within your budget (or in the case of the latter, option D, your skill set). I do not know what sort of user-incurred damage protection AppleCare offer at this time, nor when you purchased your device. No matter what, you will need to read the fine print carefully.
If the device is functioning normally, you have a fifth option, E.) continue using the device in its cosmetically damaged condition.
Now if you had a broad coverage personal electronics insurance policy on this particular device, you probably wouldn't be posting this because such policies are expensive enough to not to go unnoticed, so I assume you do not have such a policy. That would have been your sixth option, F.).
Your call.
*Some better credit cards like AMEX Platinum, AMEX Blue and others will cover out-of-warranty damage repair/replacement, a.k.a. "New Purchase Protection" for a short period of time after purchase, like 30-90 days (the latter for AMEX). That means if you buy an iPhone with an AMEX Platinum and you drop it ten minutes later in the Apple Store parking lot, shattering the screen into pieces, AMEX would cover the replacement up to a certain amount (like $1000).