When you buy an ebook using your Kindle, there’s a 99% chance it’s a DRM file. That means you won’t be able to read it anywhere else but on your Kindle. And we won’t accept that. To be able to convert that file and remove its DRM protection, you need a set of Python scripts called MobiDeDRM.
Now open your Kindle and type 411 on the keypad. This will bring up a window containing information. Write down the 16-character alphanumeric Serial.
Through your computer, buy a book from Amazon.com and save it to your harddrive. The filename shoud be something like Book-Title.azw.
Be sure you have Python installed in Linux. In Ubuntu you can easily install it with sudo apt-get install python.
Extract de files from the MobiDeDRM.zip file and run one of them like this:
python kindlepid.py XXXXXXXXXXX
where XXXXXXXXXXXX is your 16-character Serial. The Terminal window will return something like
Mobipocked PID for Kindle serial# XXXXXXXXXXXXXXXX is Z1QFCDQ*74
That “Z1QFCDQ*74” string is what you need.
Now all you have to do to remove the DRM from the .AZW file is:
python mobidedrm.py Book-Title.azw Book-Title.mobi Z1QFCDQ*74
In a minute or so you should have a DRM-free MobiPocket book you can later convert in any other format you like. If that doesn’t work, try
python mobidedrm2.py Book-Title.azw Book-Title.mobi Z1QFCDQ*74