You're getting all kinds of things wrong here.
  1. ISBNs are not sequential. The last digit is a crude checksum. So if 0901690548 if valid, 0901690549 is guaranteed to *not* be valid;
  2. The last character can be an X or a digit;
  3. ISBNs beginning 0 or 1 are not US books
I suggest you fire up your trusty google and learn some more about the structure of an ISBN before you go any further.

In reply to Re: Perl Amazon War-Dialer Script by DrHyde
in thread Perl Amazon War-Dialer Script by osmaster

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