I use Digibuy.com for my ebooks. You can upload your ebooks to their servers AND they allow you to choose to feature each book separately or to bring up a shopping cart system when you click on the buy link.
They're a bit pricey, however, charging a fee of 13.25% of your ebook price or a minimum of $3.00, whichever is greater. But, their service is good and I've not any problems with them in 9 months. Also, they mail a check on time each month, which is nice. They also have a great tracking system so you can see how many sales you've made each month, their fee and what the final check to you was. I also receive an immediate notice of when someone purchases a book, their name, address, email, phone number, etc.
You can check them out at http://www.digibuy.com
Hope this helps.
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