httpd on redhat is apache.
Have you thought about moving a better support language, eg. PHP. There's a ASP2PHP converter if you already have code in ASP http://freshmeat.net/projects/asp2php/
If you must run ASP. You'll need the Apache::ASP module. from http://www.apache-asp.org/
You do not need to reinstall apache to install a module usually. The only exception have encountered is modssl for https support.