Yup, take your daughter with you.
I would recommend new, but your budget may dictate your options.
Ask for help from the staff at each store's kiosk. They are staffed by their usual salespeople, so they (usually) know what they are doing.
Finally, don't necessarily take the first option you find that fits your needs and budget.
There are all the major retailers from the GTA at that show. Canvass a few before making your purchase. There's nothing more annoying than buying, then finding something more/equally suitable at a lower price down the hall.