How do you change the parking lamp bulb on an 2001 rav4?

Get the lamp from your local auto parts store (they were less than $5 here). I'm assuming by parking lamp, you mean the ones (the parking lamp and signal lamp share the same "bracket") low on the bumper below the headlights.

Lights OFF - these bulbs are very hot! Philips screwdriver - loosen both screws on the lens cover and the bracket will the swivel out towards the side of the RAV. At the base, there are 2 cables going in. Grasp the base of the cable and twist slightly (I think it was counterclockwise) and the bulb assembly pops out. From the base of the bulb, pull it away from the assembly and put the new one in. Replace the base of the bulb assembly into the bracket and place bracket back on the Rav and tighten screws (may want to check that they work first so you don't have to loosen screws first)