asp.net ajax sql/mysql database web application

I am looking to create a clean, modern looking web app that utilizes sql database operations. I basically want to make a pay to edit wiki based on a book's structure. Each "page" of the wiki is about one sentence long and contained in a database. Users can find the sentence they want to edit by either searching for particular words, or by selecting it's location by | Chapter | Page | Line. ? Scope: The database is not gigantic and at this time only contains one large book. About 40,000 sentences will be contained in the database. All 40,000 sentences will be editable. The search feature would include a highlight search terms feature like google. A user will visit the site, and either search for specific words in lines of text in the database, or use dynamic drop downs to navigate to those specific lines of text. ? The user will then be able to "edit" the chosen lines of text. The screen will show the database row containing the line of text previous and after the select it (so that the line of text makes sense contextually). ? The page will also show what the original line of text was, what the line of text is currently, and then give a text box for editing. ? There will be simple things kept track of like number of edits, who edited, time edited. In order to edit, the user must pay a fee through a simple payment processor like paypal's website payments standard.? In summary, a nice looking asp.net website with simple database operation. ? utilization of a technology like ajax is wanted.