well to aply textures to it you should UV map.. there is lots of stuf about UV maping. to use shaders though its not as hard.. but shaders don't work really good for organic things. To get the streaches out you need to move the UV points around so that more of the texture gose to thoughs poly faces that look streached.

can we see a wire frame of your model ? I don' t know if the printScreen key works with the PLE..