One or all three of your belts (A/C compressor, power steering, or generator/water pump) is worn or really, really dry. They are easy to replace... direct access, no prep. Cheap too, under $10 a belt on rockauto. You can also buy some belt dressing and spray them if they are still usable (visually inspect per the manual).
I had the exact same sound on every start up around 110,000, belt dressing would get rid of the squeal for like 2 days, so I replaced them. They were really worn out. Haven't squealed in 40,000 miles.
01 SE 4x4 Auto