Hi Laura. Michelle seems to know a lot more about Story Something than I do. She even made a sale to them (congrats, Michelle!). The link she provided in her response to your question will give you the same information I have regarding guidelines, pay, etc. I thought it sounded like an interesting concept, and since I had a story that I thought might fit the 8+ age group I sent it in on August 23.
I did receive an auto-response that said they try to respond quickly and would get back within 10 business days. However, Michelle is concerned now because a second story she has out to them has never been responded to. Hopefully this doesn't mean they are no longer a viable market.
Guy