To begin, I have read both Is there a way to get a Kindle Fire to work with 12.04? and How can I transfer files to a Kindle Fire with a Micro-USB cable?

My problem is that I am unable to mount my Kindle Fire in order to add books to it. I have installed calibre, but it is unable to manage any devices until the computer itself has recognized it.

The latter post had an excellent answer (provided by @jeremiah) that was making some progress. Unfortunately, I think I don't know enough about the -t flag used with mount.

This is what I've done...

Ran dmesg to locate the device:

[    3.920886] sd 6:0:0:0: [sdb] Attached SCSI removable disk

Confirmed it's location:

$ sudo ls -l /dev/disk/by-id
lrwxrwxrwx 1 root root  9 Aug 18 15:52 usb-Amazon_Kindle_3C6C002600000001-0:0 -> ../../sdb

So we know that my Kindle is recognized on /dev/sdb. I then used the mount command suggested by @jeremiah:

$ sudo mount -t ext3 /dev/sdb/ /mnt/kindle/
mount: no medium found on /dev/sdb

The same error occurs for sudo mount /dev/sdb /mnt/kindle.

Note: I have created the 'kindle' directory in 'mnt'

Any suggestions?