You might do better with some of more reputable nurseries. Try Chiltern seed for example. They offer a mix of Sempervivum seed. Don't start the seed until February or March though. There are instructions for seed growing on this site. Most of the seedlings won't be as interesting as the named cultivars but this will help your technique for more valuable seed and plants.
If you live in Portland you should come to our Hybridizers Clinic in April. You will see more semps than you thought possible.
Kevin
