You can read the Cisco IDS Command Reference at http://www.cisco.com/application/pdf/en/us/guest/products/ps2113/c1051/ccmigration_09186a008019d6c1.pdf.
The Cisco IDS Appliance and Module Installation and Configuration Guide appears at http://www.cisco.com/application/pdf/en/us/guest/products/ps2113/c1679/ccmigration_09186a00801a229b.pdf.
Release notes for Cisco IDS version 4.0 appear at http://www.cisco.com/univercd/cc/td/doc/product/iaabu/csids/csids9/15284_02.pdf.
For an introduction to the Cisco IDS, visit http://www.cisco.com/univercd/cc/td/doc/product/iaabu/csids/csids5/csidscog/overview.pdf.