but some 2960-X (http://www.3anetwork.com/
only 2 3560X are showing up.
what is required for the 2960-X to show supported?
If you're running the latest CNA (as of this posting that's version 5.8.9 - released 25 Nov 2013), it has support for most variations of 2960-X.
See the Release Notes from cisco.com: http://www.cisco.com/
If you're running an earlier version, you'll need to upgrade.
Catalyst 2960 and 2960-S switches are the leading fixed-configuration Layer 2 edge access switches, 2960 is FE access switch while 2960-S most ports are GE. The Catalyst 2960-S Series Switches are stackable switches and support POE+ function. 3Anetwork.com keeps stock for most 2960 and 2960-S LAN base switches. Among all Cisco Catalyst 2960 switches, WS-C2960-24TT-
More related for Cisco Switch:
Difference between the Cisco 2960 and Cisco 2960S (http://www.3anetwork.com/