Hi Datta,
I would suggest to start from here for basic TS and reference user guide for detailed information and configuration examples.
http://docwiki.cisco.com/wiki/Cisco_Application_Control_Engine_%28ACE%29_Troubleshooting_Guide_--_Overview_of_ACE_Troubleshooting
Also, ACE is EOS and EOL and this product line has been discontinued by Cisco. While you can still learn about loadbalancers and how they function etc, i wouldn't spend too much time learning this product specifically.
Regards,
Kanwal
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