Not sure how to get ebook files on your device?
.mobi format is for Kindles/Kindle app devices.
.epub format is for most other devices/platforms.
If you’re using a Kindle or Kindle app: http://www.amazon.com/gp/sendtokindle
If you’re using a Nook or Nook app: http://www.barkingrainpress.org/faqs/load-epub-nook/
If you’re using a Kobo: http://www.kobo.com/help/en-US/article/748/transferring-ebooks-to-a-new-kobo-ereader
If you’re using an iPad or iPhone, download the file, then select “open in Kindle” or “open in iBooks”.
Note: I cribbed this from L.T. Vargus in an email promoting their book downloads.