I apologize in advance if this has been asked before, but how do you find out what coins were worth a year, five years ago, ten years ago? I know I could go out and buy old red books, but they only give you a partial snapshot. I would love to know for instance what my $5 gold piece auctioned off for in 2004. I'm not sure that's available now, or is it? Thanks for any help.
You could search the Heritage site (and other auction sites) for completed autions. I'm not sure but I would think you can limit the search to a certain timeframe.