We have baby signing books by Linda Acredolo for parents and board books for babies. We started signing with ds when he was about 6 months and he started signing back "all done" when he was around 9-10 months. Then nothing, and we were a bit frustrated, until 13 months, and he basically EXPLODED with the sign language, learning by himself from the board books (with reinforcement from us). It was like all of a sudden he wanted to communicate. He now does signs ALL THE TIME, about 30-35 of them. It is so cute, and so nice that he can tell us what he wants or what's on his mind (he's 15 months now). It's really great!
The books say don't start until they're about 6-7 months, because you won't get a response and you may get frustrated and give up. Don't give up! It's so worth it! Some babies pick it up sooner than others. It's important to start small - only one or two signs. We did "all done" and "milk" but he only picked up the all done sign. Then we introduced "food" and "drink" (different from milk, which was BFing). Because he didn't do those until later, we didn't introduce any more. One of my friends tried to do too much too quickly, so her dd didn't pick up any signs.
So there's our story. If you want more info, feel free to PM me!
