"The Roman commanders advanced their javelin throwers (velites), who moved ahead of the infantry and discharged their missiles, the Gaesatae were soon in difficulties. The shield used by the Celts does not cover the whole body, and so the tall stature of these naked warriors made the missiles all the more likely to find their mark. Yet if the Gaesatae were carrying the usual Celtic oval shield, they were surely well protected?
The Gaesatae found themselves subject to a murderous barrage of javelins while being unable to close with their adversaries. Some of them broke ranks, and rushed forward to engage the enemy, throwing away their lives as they ran forward and thus made themselves a more vulnerable target. The others wre pushed back on the Insubres, who were behind their ranks. They were thrown into disorder. Unable to get near the Roman ranks for hand to hand combat, cut to pieces by the rain of missiles, the Gaesatae were finally broken". -Peter B. Ellis /Battle of Telamon 224 BC.

This is what I was getting at about the lack of armor, and being in melee combat wouldnt be much different. This is the only thing I could find of actual combat involving the Gaesatae. Where can I find more information on these guys including the battles,formation, the drugs they used and etc?