Your owner's manual is the definitive source for the exact location and fuse layout. It will have a diagram showing the fuse panel and which fuse corresponds to the radio and power outlets. The manual will also show the amperage rating of the fuse so you can replace it with the correct one.
If the fuse box lid doesn't show the fuse layout, you can often find a diagram online by searching for "2000 Chevy Impala interior fuse box diagram". Make sure you specify the year and model as fuse layouts can vary even slightly between models.
Important Note: Before replacing a fuse, always make sure the ignition is turned off. Using the wrong amperage fuse can damage your car's electrical system.