Hi Craig,

you have pretty much the same set up as me. I would heartily recommend using the SB900 and the D300 in commander mode as this will meter the TTL for you. Use of window light is also worth looking about for. If there are any rooms with good window light then just move furniture about to suit your purpose. Keep any background clutter to a minimum.

As for poses etc you might be asking too much with a 3 year old as they don't tend to do what you want when you want, but a scan through FLICKR might be worth your time for ideas

rgds
Dave