You could download a snapshot of the full LC back file at the Internet
Archive (kindly donated by Scriblio).

Then run a script using your favorite MARC parsing library (mine
currently is pymarc):

  from pymarc import MARCReader

  for record in MARCReader(file('part01.dat')):
      if record['020'] and record['020']['a']:
          print record['020']['a']


On Mon, Apr 28, 2008 at 9:35 AM, Godmar Back <[log in to unmask]> wrote:
> Hi,
>  for an investigation/study, I'm looking to obtain a representative
>  sample set (say a few hundreds) of ISBNs. For instance, the sample
>  could represent LoC's holdings (or some other acceptable/meaningful
>  population in the library world).
>  Does anybody have any pointers/ideas on how I might go about this?
>  Thanks!
>   - Godmar