As a kid I loved, loved, loved paper dolls. I found a store with a whole selection of them. I was tempted to purchase something for old time's sake.
Another reason why I love Covent Garden is because my favourite museum is here too. The London Transport Museum. People are always surprised when I tell them this fact, but it's true. You go back in time to discover the history of London transport. It's just so well done. I highly recommend a visit if you haven't been already. It is a bit on the pricey side with a single adult ticket costing £15, but it's good for a year and you can go back any time to see one of their special exhibits for free.
Fun travels!