SEI offers help desk outsourcing services. Their specific competency is support for proprietary systems. Sentinel Technologies offers on-site and remote help desk support services. Stream International offers help desk outsourcing services. Support Systems Developers, Inc .
Offers help desk outsourcing.
Transworks is an India based organization that offers a variety of services includes web based chat, email support and knowledge based support. Check out Randall Pearson's site where he has made some resources available via anonymous ftp.