To delete your page, visit your page and click the "Settings" link to view the page settings.
Scroll all the way to the bottom to find the "Delete Page" button.
You will presented with a window confirming that you want to delete this page.
Please Note, when you delete your page, you will not be able to recover it. Also, someone could take this page name since it's deleted. If you want to preserve this page, consider making another user a page owner of this page.
If you are good with all of this, hit the "I Understand. Delete Page" button and your page will be deleted.