I grew wildflowers this year with sunflowers being in the mix. I never knew where the sunflower seeds were in sunflowers. I have seen sunflowers, I never saw any seeds. They apparently are in the head just past the pollen. You need to scrape off the pollen to see them, a little gardening secret apparently. If I had grown up in an area slightly more rural than Los Angeles perhaps I would have known that.
After scraping off the sunflowers (be sure to have a can ready to deflect the caterpillars you will cross roads with), soak in 1:3 salt/water solution for several hours and bake in oven at 200 for 2 hours or until they are dry. They will crack if you pinch them with your fingers instead of giving in. These flowers can have as many as 2000 seeds in each head. I am DEFINITELY doing this again next year. Darling daughter and I had a lot of fun with this one.
NOTE: The sunflowers are ready to harvest when they bow their heads and the back of the flower head turns yellow:)