Symbols are shown in red text whenever they are discussed, so you can easily track them through the work.
Hamlet is not a very symbolic play. In fact, the only object that one can easily pick out as a symbol in the play is the skull of Yorick, a former court jester, which Hamlet finds with Horatio in the graveyard near Elsinore in Act 5, scene 1. As Hamlet picks up the skull and both talks to the deceased Yorick and to Horatio about the skull, it becomes clear that the skull represents the inevitability of death. But what is perhaps most interesting about the skull as a symbol is that, while in most plays, a symbol means one thing to the audience and another to the characters in the novel or play, in Hamlet it is Hamlet himself who recognizes and explains the symbolism of Yorick's skull. Even this symbol serves to emphasize Hamlet's power as a character: he is as sophisticated as his audience.