Jewish ancestry searches aren’t so very different than those of other cultural groups, each having its own particular vagaries, however there is one very big difference, that being that, like the Russian and severaal other ethnic groups, there have been times historically when names were changed, histories were rewritten or records were lost, most notably during the war years.

Not every country, or culture has good records of their existence and some of them, in all honesty, have been pursued or persecuted to the point that in some instances it didnt’ pay to relate or keep abreast of family histories.

Jewish history, as well all know has some instances of this, much like Native American, Russian, and other cultures does.

There are multiple sites available online to assist you in getting started to gather information on your Jewish background, among them one that several friends of mine have called invaluable, when tracing overseas as well as in the United States.
Ted Gostin, who is a professional genealogist recommends several means of tracing your Jewish history, among them:
birth, death and marriage records, U.S. Census Searches, U.S. Naturalization Searches, (these are particularly helpful in many cases because they also provide names of children, spouses and the date and place where everyone arrived) U.S. Passenger Arrival Records Searches, such as the primary ports of entry into the United States.

European records that you might choose to work with are:
the census records that many Jewish Communities kept in Europe,such as those that are available from Poland, Hungary and Germany, many of which you can access in the US via the Family History Library that exists in Salt Lake City.

Also helpful to you may be the Business and city directories for cities in Europe in past days as well as the Jewish communities Yizkor books, which not all Jewish communities keep, but which does document the history of their town and the destruction, if any, of the Jewish Population
While not the definitive authority, many of these valuable books have documented entire family histories unknowingly.

It is, to our great sadness, a fact that many Jewish people will eventually discover that someone in their family was likely a member of the holocaust victims, or a survivor of the same.

Those records too can be helpful, such as survivor lists, deportation lists, victims lists and other holocaust documentation.

Tracing Your Jewish Ancestors, A Guide, which is a Gould book is well worth your time and investment to get your hands on if you are interested in tracing your own ancestry or someone elses.

One of the greatest sites to assist you in finding your Jewish heritage will be the Jewish GenWeb Site wh ich offers not only information, but also assistance by other members of the forums and the site, and from whom you can glean advice on where you should begin with your search.