Once you have your ebook, there are a lot of ways to reach your target audience on the web.
For instance, two of my ebooks are on a site that specializes in ebooks about alternative energy and resource conservation - http://www.ecobrain.com.
Google topics like "ebook promotion", "ebook sales" and "ebook stores" and you will find a lot of resources to help sell your ebook beyond the traditional sites like Amazon. For "how to ebooks", clickbank is an excellent way to go. Here is my link to clickbank:
http://tmcco4316.reseller.hop.clickbank.net
Good luck with your ebook.
Sincerely,
H. Court Young
Geologist, author and publisher
Promoting awareness through the written word
http://www.hcourtyoung.com
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