There are a number of aftermarket auction sites where some domain names may be purchased from their current owners.
If you are looking for a specific domain name, the best way to determine if it might be for sale is simply to try to visit the web site at that domain. If the domain is for sale, there is a good chance there will be a link at the top of the page which takes you to the listing for that domain, wherever it may be.
If the domain name is not listed for sale, you can try to make an unsolicited offer on the domain. This is a special option provided by only a few of the aftermarket auction sites, such as Afternic.
There are a couple of good sites to search for domains that may be for sale:
There used to be three other pretty decent domain name auction sites, but NameWinner has discontinued their auctions and the other two have discontinued their affiliate programs.
If the domain name that you are intersted in is not listed for sale, another option is to monitor it and/or backorder it. With monitoring, you will be notified whenever the status of the domain name changes, such as if the domain name goes past its expiration date, or into "pending delete" status. With a backorder, a registrar will attempt to acquire the domain name if it ever gets released.
Some places where you can place a request to monitor or backorder domain names include:
Home > Internet > Domain Names > Domain Auctions
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