The best, and easiest way to get seeds and buds from the same auto plant is to grow some regular seeds, not fems. Take pollen from a male and use it to pollinate one or two of the lower branches on a female. When the unpollinated buds are ready, harvest them and leave the seeded branches until the seeds are fully mature.
Yes you are right Muddy...I'm doing this experiment strictly out of curiosity. It was fascinating to watch a branch with preflowers actually take root and grow, and then switch over and start producing male flowers with the C/S treatment!
Easiest way to get seeds......buy 'em!! But it's good to know about all the options too.