However, it's almost always located on top of the power steering pump, which is typically found in the engine bay. Look for a reservoir that's usually plastic and cylindrical or rectangular, often with a dipstick or markings indicating the fluid level. The cap will be on top of this reservoir.
To be certain, I recommend:
* Checking your owner's manual: This is the best resource. The manual will have diagrams showing the location of all fluid reservoirs.
* Searching online for a 1996 Oldsmobile [Your Model] power steering diagram: A quick image search with your specific Oldsmobile model (e.g., "1996 Oldsmobile Cutlass power steering diagram") will likely show you a picture of the engine bay with the power steering reservoir clearly marked.
Without knowing the exact model of your 1996 Oldsmobile, it's impossible to give a more precise location.