if your looking to customize the radio station list on the radio blaster you can find the tutorial here - HE Streaming Radio Player Instructions ›

as for changing the texture you do it just like adding a texture to any product, the texture that comes with the radio blaster is a 4 frame cycling film strip...

if you want to change the sprite graphic you can find the place to add your png on the particles tab...

you can find the imvu creator tutorials here - Creator TUTORIALS