There are a number of excellent online resources to help you keep up-to-date on who's running in your area as well as the logistics of voting locally or by absentee ballot.
Primary Voting in New York
New York has a closed Primary voting process. This means that in order to cast a vote for who the eventual party nominees become, you must be registered with that party.
If you are registered as an Independent, and wish to vote in either the Republican or Democratic primaries, you can re-register to state your preferred party.