Here are the most common honorifics and terms of address.
 
   -sama    Very respectful ending.  Not normally used with someone's
            names.  Used to people of superior status, like your boss,
            or to your guests as a host.  Envelopes should be addressed
            with "-sama".  A shopkeeper might call a customer
            "o-kyaku-sama" (Respected Mr. Customer).
 
   sensei   A respectful term meaning "teacher", also used with
            physicians.  Frequently used to refer to experts in a
            field or people in any respected occupation.  Lawyers,
            master chefs, fashion designers, and even some manga
            artists are called "sensei".  Sometimes used like an
            honorific with a name or title, as in "kouchou-sensei"
            (Mr. Principal, Sir).
 
   -san     Usual term of respect.  It can stand for Mr. and Ms., and
            is attached to either first or last names, and names of
            occupations like "o-mawari-san" (Mr. Policeman).  You
            use it for strangers and people you don't know well, but
            are more or less the same social status.  When in doubt,
            use "-san".
 
            However, never use "-san" with your own name or your
            family members' names.  Also, it shouldn't be used to refer
            to famous people, since a small degree of intimacy is
            implied.
 
            High school girls are usually called "-san".
 
   sempai   Somebody in the same general social class, but socially
            superior to you.  "Sempai" can also be used as an honorific.
 
            Older students may be addressed respectfully as sempai,
            especially by girls.
 
   -kun     Used by a socially superior male to a socially inferior
            male.  Familiarly used among male students and boys who
            grew up together.  Recently, some teachers call girl
            students and some bosses call office ladies with "-kun",
            but it's still considered a masculine suffix.
 
            High school boys are called "-kun".  Girls go from "-chan"
            to "-san" in high school, but boys go through a period of
            "-kun" in between.
 
   -        Calling someone by a family name alone is being very
            familiar (or rough).  Calling someone by given name
            alone is less rough, but more familiar.  Using no
            honorific when one is expected can be an expression of
            contempt.
 
   -chan    Intimate form of address.  Families that are close use it,
            and "-chan" is often used to, and by, very young children.
            Used with given names, abbreviations of given names, and
            nicknames, but not family names.  Children who grow up
            together (like Madoka and Hikaru), may keep using "-chan"
            into adulthood.  Note: to call a social superior "-chan"
            without reason is very insulting.
 
 
Family terms are also common terms of address.
 
(Note:  One may sometimes identify a person by taking the listener's
 point of view, as when a man refers to himself as "father" to his
 children.)
 
                Referring to                    Addressing
                yours           someone's       yours (*)       someone's
 
grandfather     sohu            ojii-san        ojii-san        ojii-san
grandmother     sobo            obaa-san        obaa-san        obaa-san
uncle           oji             oji-san         oji-san         oji-san
aunt            oba             oba-san         oba-san         oba-san
elder brother   ani             onii-san        (o)nii-san      [Name]-san
elder sister    ane             onee-san        (o)nee-san      [Name]-san
 
These six forms of address occur a lot.  Children call strangers
by the above family member terms, depending on whether what type of
relative they consider them old enuf to be.  (A good example of
this is a scene recently described in this newsgroup where a child
addresses a question to a young woman as "oba-san", and she responds,
referring to herself as "oNEE-san".)
 
father          chichi          otou-san        (o)tou-san/papa otou-san
mother          haha            okaa-san        (o)kaa-san/mama okaa-san
younger brother otouto          otouto-san      [Name]          [Name]-san
younger sister  imouto          imouto-san      [Name]          [Name]-san
daughter        musume          ojou-san        [Name]          [Name]-san
son             musuko          musuko-san      [Name]          [Name]-san
wife            tsuma/kanai     oku-san         omae/[Name]     oku-san
husband         shujin          goshujin(-sama) anata           goshujin(-sama)
                                                                [Surname]-san
 
Some ways of saying "you":
   otaku        very polite
   sochira      very polite
   anata        polite, common (*)
   kimi         informal masculine pronoun, common (*)
   omae         very informal or rough (*)
   anta         very informal or rough contraction
   temae        very rough  (Note: can also mean "I")
   onore        very rough  (Note: can also mean "I")
   kisama       very rough
 
Some ways of saying "I":
   watakushi    very polite
   kochira      very polite
   watashi      polite, common (*)
   atakushi     polite feminine contraction
   kotchi       polite
   washi        informal masculine contraction, used by old men
   atashi       informal feminine contraction
   boku         informal masculine pronoun, common, used by boys/young men (*)
   uchi         informal feminine
   ore          very informal or rough
 
I've marked with a * the ones that come up frequently.  Learning them
will make watching unsubtitled anime more pleasant, but there's no
need to memorize them, all at once.
 
You may notice that the very rough words for "you" are often
translated as curses.  These are pronouns that insultingly imply
the speaker's superiority.  They come up often as fighting words.
 
                        - From a posting by Theresa Martin