Ian Holloway brought his Eagles to Yorkshire top of the Championship, but goals from Luciano Becchio and Paul Green ensured a morale-boosting win for the hosts.
Warnock was quick to highlight the contribution of experienced defender Tate, on loan from Swansea, and pacy winger Thomas, who has joined the club from West Brom.
Warnock said: "I am absolutely delighted for the new owners. We deserved the win over the 90 minutes.
"We started the game very well and had to hang in there at times but our two new lads made the difference. Alan Tate is a good pro.
"He had a calming influence on us at the back and Jerome Thomas is as good as anyone in the Premier League, let alone the Championship. We needed the lift in confidence those two have given us."