Here is basic crash course to Jewish genealogy.
We all have many ancestral families. Be sure to treat each family as a separate project. For each family name do the following: Do your homework. Interview your elder relatives. For each person try to write down at least:
- Names: Record every name you encounter, including parents, siblings and children.
- Places: Record birth place, place of death, place of marriage if available.
- Dates: Keep track of dates of birth, death, marriage. If information is not available, set estimated year of events based on educated guess.
- Spouse's full name including maiden names, spouse's parental names and their place of origin.
Which brings you here:
Keep this information safe and revisit it to make changes based on the newly-researched information.
Identify locality where your family comes from. Notice the name of the district and provincial centers. Records are often grouped by district so you need to aware of its name to see if any particular set of records is worth looking into.
Primary genealogy data sources includes censuses and vital records. You have most chance of finding family members listed in those. Identify which records have survived and for what years. Often this step is already done for you.
Some families would stay in one place while others migrating in every generation. Don't despair. Examine each newly found record in great detail. Census records often include age at the previous census. If this information is present it already extends your knowledge of when your family lived there by that many years. Otherwise if you lucky there will be a comment recording when your ancestor moved there.
Similarly for the vital records. While many Jews were recorded in their communities, some others made it to the nearby larger towns. Whether it was for better hospitals to give birth, marry someone from out of town or find a final resting place when local community lacked Jewish cemetery, great many Jews from out of town are recorded in many district and provincial centers.
Think in clans not family lines. Your family history does not exist in one file because you never recorded it. If your last name is rare, expand the search geographically to include at least the district to yield more results. Examine all people found against information from your homework noticing common naming patterns and years before either accepting or rejecting individual. Keep the separate file of found individuals whom you could not prove to be related and take a habit to re-examine it few times a year based on newly-found information to help pieces of puzzle to fall in place.
With more and more records becoming available and translated often in the way of the last name indexes you can quickly scan through and cross out records from your list thus saving you both time and money.
One place to start is here. I do genealogy research so that you don't have to.