DNPric.es | Domain Name Prices, the most complete database of 1,000,000+ [premium] online asset sales worth $6,000,000,000.00+ of deals and much more
HotBot.com Banks $155,000 to Top This Week's Domain Sales Chart - .Coms Sweep All But Two Entries
DNJournal.com YTD Top 100 Domain Sales Chart
Can get ballpark ideas from archived sales but at the end of the day a domain is worth whatever the right buyer will pay for it. Buyer A may pay 1k where Buyer B may pay 5k. Finances of the seller comes into play as well. If he needs the money may sell, if he's financially stable may have the patience to wait for the right buyer to come along which may happen or might never happen but can afford the gamble of holding out. Been buying & selling domains since 2003, currently 526 in stock mainly mainstream.