software and code information

[Beatriz Margolis]

I would appreciate if somebody in the list could help me with the following
questions:
    a. Where may I found a description of the internal format of a .xls
file?
    b. Does there exist a free software able to translate .xls to .txt or
.bin ?

You can answer to me directly. Thank you very much.

Beatriz Margolis
email: [EMAIL PROTECTED]