Can someone help setting up snmpv3?
Yes: some manual might be the best help.
Honestly: when i entered "AIX snmp redbook" in ixquick.com (i shun google) i got several gazillions of hits. Following just two of them revealed:
Systems Administration Toolkit: Using SNMP data
The second one is quite often pointed to in other references and should (despite the title, which suggests differently) deal quite a lot with SNMP.
I hope this helps (in more than just one way).
bakunin