I found the following links dealing with file conversions. It looks like you can read the Mobi format on the older Kindles, and .pdfs on newer ones.
http://ireaderreview.com/2008/01/18/how-to-view-pdf-files-on-the-kindle/
Thank you, Meg! I'm glad to hear that. I've felt sort of helpless because I don't have a Kindle myself, I have the Sony and I read on my BlackBerry too, so I figured I'd better educate myself so I could answer questions. *LOL*
Lesli.
I also received this from a fellow author who asked one of her Kindle readers about the issue:
When I get a book that is .pdf, I email it to Amazon. Normally the
email address is something like mine (xxxxxx@free.kindle.com) and they email the converted book back to you within a few minutes. I then plug the USB cable that came with the Kindle to my computer and download it to Kindle. There is also a way to do it where it is sent directly to the Kindle from Amazon, but they charge like .15 to do it and I've never done it that way.
You can also purchase from other places like Fictionwise, EC, MBaM - you just pick the Mobipocket/prc format and download it to the Kindle using the USB cable.
I have been downloading your books to my kindle for a very long time (to my computer first then to the kindle)and have no problems.I have a first generation kindle! Meg