1. ancestry.com – I got the world membership and also did the DNA test. The DNA test has not proven fruitful yet; there are many matches, but I can’t figure out how we are connected. It is not helpful that I can’t link my tree to my DNA test, because I’m only an editor of the tree and not the owner. The regular site is extremely useful, though. I have found a lot of information there; searching is easy and powerful; the amount of data is vast.
2. newspapers.com – I only just started using this site and haven’t paid yet. The searching is painful, especially if the subject has a common name, but it is a good resource for filling in gaps and finding interesting tidbits.
3. jewishgen.org – a very old site (the design shows it), but it provides a way to get in touch with other genealogists researching the same names/regions. So far, I have not found it very beneficial, but it seems very useful if you actually know anything about your more distant Jewish ancestry.
4. rootsireland.ie – database of Irish church and civil records. Some counties are very thorough and others are not. It’s a pay per view service, and rather expensive if you aren’t sure what you’re looking for, but it has a lot of information that I haven’t found elsewhere.
5. italiangen.org – has indices of a number of useful collections of genealogical data in the New York area, particularly New York City vital records. When I first started, I relied on this for NYC records, but lately Ancestry.com has been adding some of these indices.
6. NYC Municipal Archives – You can go in to look at records on microfilm or pay $15 to have them make a copy and mail it to you. You can find the certificate numbers from italiangen.org. Not everything is indexed on italiangen, though.
7. Yad Vashem – database of Holocaust victims. It occasionally has useful source citations for the names, and often has hometowns. It is only helpful for Jews; they don’t list members of other groups that were murdered by the Nazis.