To find it, you'll likely need to:
1. Consult your owner's manual: This is the best place to start. The manual should have a fuse box diagram showing the location of the flasher relay.
2. Look in the fuse box under the dash: Many Grand Ams have a fuse box under the dash on the driver's side. Open the fuse box cover and check for a relay that's labeled "turn signal" or has a similar designation. It might be a small square or rectangular component.
3. Check behind the dash: If you can't find it in the fuse box, you may need to carefully remove some panels under the dash to look for the relay attached to the wiring harness. Be sure to disconnect the negative battery terminal before doing this to prevent electrical shock.
If you're uncomfortable working on your car's electrical system, it's best to take it to a mechanic.