Because its exact location can vary slightly, it's best to:
1. Consult your owner's manual: This is the most reliable source for your specific vehicle.
2. Look carefully along the passenger-side floor and under the dash: Feel for a small, usually square or rectangular, black box. It often has a button that can be reset.
3. Search online: Search for "1997 Buick LeSabre fuel inertia switch location" with images; visual confirmation can be very helpful.
If you can't find it after checking these places, a qualified mechanic will be able to locate it.