Got mine online from http://www.lightningmotorsports.com/piaa_bulbs.htm, you can also somtimes find them on ebay, but I've never seen them in a actual store like autozone, pepboys etc. Keep in mind, there may be others that fit, but the w2 is the only one I've actually tested and have had no problems with the wattage melting the assembly. They also have the replacment dome lights and the replacment marker wedge bulb.