SketchUp’s Match Photo feature can help you apply a photo to your model, or even create a model from a photo.Match Photo works best when your image meets certain criteria:

Materials, environments, and textures add images, colors, lighting, and textures to parts of your model. Applying these effects to your models adds an extra level of detail and realism. 

3D Warehouse provides a few ways for you to find the materials you are looking for. You can always search for a material and download it into your model. You can also download materials used in the models that other users have added to 3D Warehouse. To download a material used in another model without downloading the whole model, follow these steps: