To be certain, you should:
* Consult your owner's manual: This is the best resource for the exact location.
* Use a repair manual specific to your 1996 Buick Regal: These manuals often have detailed diagrams showing the location of all components, including the EGR valve.
* Search online for diagrams: Search for "[your engine type] 1996 Buick Regal EGR valve location" on Google Images. Look for images of the engine bay with the EGR valve clearly labeled.
Remember, working on your car can be dangerous. If you're not comfortable locating and inspecting the EGR valve yourself, it's best to have a qualified mechanic do it.