I searched the WEB and didn't have much luck either looking for 'shade designs' or 'shade plans'. The only plans I could find had to do with outdoor lighting and gardens.
You may have some luck visiting a nursery. Either look for books or ask for 'types' of shades. That might help you find plans on the WEB. I'm not talking about just going to Home Depot or Lowe's or something. I talking about going to those places AS WELL AS a Nursery. Nurseries are lised in the YELLOW PAGES under NURSERIES.