Japanese pronouns are frequently omitted in speech -- context makes clear who or what is being referred to. Personal pronouns do not change for case. That said, the basic list of personal pronouns is as follows:
"I" or "me". Often contracted to watashi; or atashi (women only).
Plural form is wata(ku)shitachi, which indicates "we" or "us".
Also means "I" or "me". More casual than watashi or watakushi. Used mostly (but not exclusively) by men and boys.
Plural: bokura or bokutachi.
Translates to "you". Rarely used, compared with English. The name, position, or title of the person being referred to is usually used instead.
Plural: anatatachi or anatagata
Also means "you". It is more casual than anata. As for whether this pronoun is actually used much (compared to anata) in colloquial speech, I don't know.
"He" or "him". The title, position, or name of the person referred to is usually preferred.
Plural: karera, "they" (masculine or mixed).
"She" or "her". Again, title, position, or name is usually preferred over this pronoun.
Plural: kanojotachi, referring to a group of females.
ano hito
Often used for "he", "she", or to mean "that person" (the literal meaning). This is more common than the previous two pronouns for referring to a third person.
Plural: ano hitobito or ano hitotachi, which indicates "they" or "those people".