I am looking for a list of library services companies/librarians who
would be able to classify books into a given scheme. 

Specifically what I am looking for is a list of links to low-cost
businesses and also master lists of librarians who I would be able to
solicit for classification of about 4000 books. This would all be done
over the web- most likely using amazon.com as the source for book
info-

Cost is an issue here, so offshore companies would also be welcome
here. Payment available for additional answers and direction if they
are more useful (via Paypal, but at reduced price)

What scheme Dewey decimal, Library of congress, or?

Here is a company in India which does a lot of indexing work for two
US based companies that I know. You might want to check them out:
www.btsworldwide.com

Hope this helps.

Skt1479