You just never know when you'll find a good pattern. I mean, why bother with compasses, folding paper and using scissors when perfect patterns are available everywhere around you? (This is cooking directions in a pizza dough package.)
One of my favorite patterns for a spout, like the one pictured on the square teapot at the top of the blog, came from a label on the side of a Ketchup bottle.
The best thing I've found for making really tough templates is x-ray film. That's not so easy to come by, but if you can find a supply, hoard them! I just happened to see a bunch in a trash can when I went to have my annual mammogram and asked the tech. if she would give them to me. (Now I know that most places send them somewhere to have the silver reclaimed, but evidently this place didn't know or didn't care to do that.)
Another good place to Med-Scavange is from you friendly neighborhood dentist. Old, worn out dental tools are great. Made of good materials, easy to clean, non-rust steel--can't beat that. It's getting more difficult to find them because of concerns about disposal/contamination/liability , but it's worth it to ask. If all else fails, you can probably find them on eBay. Everything else is there.