Re:
I have an Islabike Luath 26, which Islabike identify as suitable for 9+. I got it (in 2009) for my son's 10th birthday. It was a good fit for him, and he's pretty small for his age. They're well thought-out, with brake levers that are well suited to small hands, etc. It has 26" wheels, and I think it may be a 17" frame, but it is sloping and I would have to check measurements.
Let me know if you might be interested, and I can supply more info.
Nick