Dear Divya,
You can get the DDC no for the titles from the Library of Congress, British Library ....

Click for Library of Congress Online Catalogue
http://catalog.loc.gov/cgi-bin/Pwebrecon.cgi?DB=local&PAGE=First

Click for British Library Integrated Catalogue
http://catalogue.bl.uk/F/9T8VCPAAY3QFCUDCUFD15EANU745I4FIEBJYLYPUT129RH6VIA-01040?func=file&file_name=find-b&local_base=BLAC

Thanks and Regards

Ajay Kumar Sharma
Project Associate, INDEST-AICTE Consortium
Central Library, IIT Delhi
Hauz Khas,
New Delhi-110016
011-26591467 (O)
09899339808 (M)
Web: http://www.geocities.com/ajaysharma_lib/