I use sketches all the time. I found a bunch for free online and printed them. I put them in page protectors and put them in a binder. Makes it easy for me to put them out and use them and then put them back in the binder. There are free sketches in the gallery as well. If you are a pinterest user, I have TONS of sketches on there as well. I have a whole board full!!!
They have thousands of sketches here in the gallery. YOu can print them out. They are not in the layout section though. I think they are in the section other projects maybe. I did not know they had that section till last month. it is cool