Front engine sounds?

[lowesguy]

Took the truck for a short ride today,strange sound coming from front side of engine,does a click ,click,then a whirling siren sound,like a bearing going south,lifted the hood to listen and seems on the left side of engine,hard to tell what it is? I suspect alternator bearing, smog pump,or water pump bearing,comes and goes,thought it was loose belts,but I tightened them ,still the sound happens,only once warmed,I plan on taking the belt off and hand spinning each accessory,see if I can hear it. weirdest sound I've ever hear on my truck in 20 years!
did get some nice pics thou!