My experience has also been that it is rare to find S. dorrii seed, but much easier to find the plants. Your best bet may be as Wantonamara suggests: the salvia forum here, and you can also try the Yahoo salvia group which has been established longer and may have a bigger audience. I believe I had some awhile back from a trade with someone, but they never germinated. I suspect they have some dormancy mechanism. They are easy to grow as plants though, depending on where you are located.