I've been heading down to Kensington Market here in Toronto (a bohemian/hippie district) and just buying up my own herbs and mixing my own tea.
Lately I've been using a mix of chamomile, passion flower and peppermint for flavour. Not too different from what you'd find in Organic Nighty Night or any other brand of herbal sleep aids, but I find using the raw herbs makes for a much stronger tea.