Unless your LRF files have a lot of images, there isn't any way that 19 books should be filling up your reader! I have over 170 books on mine, including three different versions of both the Old and New Testaments of the Bible. It does sound like there must be something wrong with your reader's memory (since you already tried reformatting).
How long have you had your reader? It may be worth a call to Sony customer support.
Good luck-I hope you get it sorted out!
dordale
