Any specialty store, it seems. There's a collectible toy store in my local mall, which sells practically everything toy collecting - from Transformers, to Power Rangers, to old cap guns and trains. Some of the people I see in there make me angry as hell - one guy last weekend was throwing a hissy fit because the store owner wouldn't sell him a Transformers item (I think it was Masterpiece Soundwave - it's been horrendously difficult to find in any retail stores around here, apparently) for 20% of the marked cost (which would've been around $40-$50).