The most popular place by far is ExpiredDomains.net. The main advantage of ExpiredDomains.net is that it aggregates data from a lot of different auctions and websites around the web. There are also paid services like DomCop. DomCom helps you identify worthy domains faster by displaying some additional data points that allow you to vet domains easily and in a unified interface. And finally, there are services that curate domains they believe are worthy such as JustDropped.com’s newsletter.
The IP popularity and domain popularity each play a part in the overall quality evaluation. If you come across an expired domain with a high link popularity (i.e. a large number of backlinks), but then poor values when it comes to IP and domain popularity, you can assume that these links were obtained in an artificial way. Domains like these will have already caught the search engines’ attention. Perhaps this is the reason why the domain was abandoned. Users that want to start a serious online project should steer clear of these domains.
Everybody going to start using old domains should also know how to get them, I'm going to post soon article about it on seomoz as there are several ways starting from online rankings and lists up to dedicated seo tools that you can run on your computer and get precise and actual data on demand for any domains lists. Anybody intersting in such tools please visit our website: http://en.exdomain.eu/
Determine your domain's value. Before you start taking offers or listing your domain, take stock of its value so that you can come up with a good price. There are a lot factors to take into consideration when determining the value of a domain, so if you are unsure it may be wise to contact a company that performs these assessments. Some of the major factors include:
However, I'd argue that most people in the business really struggle as they don't understand what makes a good domain name and what's a bad domain name. While I do not work in this field full-time, I can say that I can make a living of it, but it's probably because I don't ask for absurd prices (e.g. randomword247.com domain name for $8000 is just unrealistic and won't happen) and therefore can sell domains easier.
Yandex replaced TCI with SQI (Site Quality Index). SQI looks similar to TCI, so I re-used the old TCI field, however all values are now the new SQI. Not all domains are checked yet, but all that had TCI > 0, are now switched to SQI and all newly added domains are also checked for SQI (starting today). Updating all domains will take a couple months.
Sometimes people purchase domains that they plan to build a website on or sell in the future, but it just doesn’t end up happening. If an individual decides that it is no longer worth the yearly investment of keeping the domain in their account, they may choose to let it expire. Or, someone might just forget to renew the domain before the expiration date. If this happens, it’s a great chance for other domain investors to score rare domain names that are pending delete. Spending time perusing the list of recently dropped domains can be a worthwhile way to find high quality domains.
Since search engines regard inbound links as recommendations, these links have a decisive influence on the ranking. The search engine definitely doesn’t appreciate link networks and won’t give new projects a jumpstart by allowing a former website’s backlink profile to be used when registering a new domain. Using an expired domain is like playing with fire, where the worst case scenario is that you’ll be penalized or be excluded from the search index.
As far as flipping domains for a profit is concerned, there are certain domain names that are worth a lot of money. For instance, Hotel.com and Business.com have been reportedly sold for $11 million and $7 million respectively. Now even though coming across such golden domain names seems more like a long shot, you can still make a decent amount of money if you choose to buy and sell domains as a part-time business opportunity.