8. One or more computer-storage media having computer-executable instructions embodied thereon that, when executed by a computing device, perform a method for providing contextual advertisements presented to a user in association with electronic books, the method comprising: receiving information to be included in a contextual advertisement for presentation to the user; identifying an electronic book including a plurality of pages; identifying content associated with each one of the plurality of pages; receiving a user profile associated with the user; identifying a target page of the plurality of pages to receive the contextual advertisement; based on content of the target page and the user profile, generating the contextual advertisement, where the information to be included in the contextual advertisement is associated with each of content of the target page, the user profile, and content of one or more pages preceding the target page; and presenting the contextual advertisement to the user.
8. One or more computer-storage media having computer-executable instructions embodied thereon that, when executed by a computing device, perform a method for providing contextual advertisements presented to a user in association with electronic books, the method comprising: receiving information to be included in a contextual advertisement for presentation to the user; identifying an electronic book including a plurality of pages; identifying content associated with each one of the plurality of pages; receiving a user profile associated with the user; identifying a target page of the plurality of pages to receive the contextual advertisement; based on content of the target page and the user profile, generating the contextual advertisement, where the information to be included in the contextual advertisement is associated with each of content of the target page, the user profile, and content of one or more pages preceding the target page; and presenting the contextual advertisement to the user. 9. The computer-storage media of claim 8 , wherein the content includes a sequence of the electronic book, a character of the electronic book, or a theme of the electronic book.