Other fora also have track-plan repositories. Try googling "model railroad forum" and look at some of the other "hits." Some other model railroad websites, run by people who do track-planning and building for a living, also contain numerous ideas. Maybe just search "model railroad track plans."
Finally, there are many books available to assist you in designing a plan for your available space. One of my favorites is "Track Planning for Realistic Operation" by John Armstrong.
Chuck