The apachesolr module for Drupal provides a first class search engine with faceted search and more. This module needs a solr server to work.
This post explains how you can install the module and a solr server on Mac OS 10.6.
Snow Leopard has already Java installed so it's pretty easy to install Apache Solr. You can almost follow the readme coming with the module but this give you a fast way ;).
Install apchesolr module