Sorry to hear about your false start. The good news is you can list your web-based business in an online auction for the fraction of the costs that a broker would charge. Business listing websites can be free or, like Flippa.com, can charge 5% of the final sale price (Flippa caps it at $498); brokers can charge 10% or more. It will help to list your site in multiple locations and check the marketplace on webmaster forums such as Dnforum.com or DigitalPoint.com. These sites will allow you to auction either your domain name or your entire e-business.
Online auctions will give you more exposure across the globe with prospective buyers within your specific industry, a valuable asset since web-based businesses can be run from any country with a laptop and Internet connection. More buyers will translate into a better price for you.
Now, valuing your site? That is an entirely different challenge. Visit http://bit.ly/ValueYourWebsite for more information about how to set a price and sell a web-based business.