Greetings Ajith,
Try an snmpwalk on ciscoEnvMonMIB and you'll see all the available objects.
Monitoring is limited on the 3560, there is no granular temperature sensor but an overtemp sensor that you can read the state of with chassisTempAlarm (1.3.6.1.4.1.9.5.1.2.13) - same data as 'sh env temp' in the CLI.
ciscoEnvMonSupplyState (1.3.6.1.4.1.9.9.13.1.5.1.3) will give you the state of the power supply - same data as 'sh env power'.
Regards,
/Phil