I don't recall but I believe that the books you mentioned are not in internal memory. They are in the internal microSD card.
If you do a search, I recalled seeing a thread about connecting to a MAC.
Another way is to open up the back cover of the IQ, you can use a credit card and start gently plying off the cover.
remove the microSD and copy it to you MAC or another SD card.
FYI, this is how the IQ internal microSD is formatted:
partition 1: EXT2 or EXT3 <--- internal memory
partition 2: FAT32 <--- this is where your ebooks are saved.