Your best bet is on eBay… if you can’t find the game you’re looking for right away, you can use eBay’s search result watch thingy, which lets you specify search terms and eBay will email you whenever an item is posted that matches your search terms. I have a number of games I’m planning to sell myself, I just haven’t got around to listing them yet, depending on what you’re looking for. I don’t have a copy of Time Zone at all. There may be other collectors on this board who also have games to sell.