Notice that except for mí, ti, and sí, the Spanish prepositional pronouns are the same as the subject pronouns. Also, take a look at the following examples:
A mí, no es importa. (It is not important to me.)
Para ella. hablar español es difícil. (For her, speaking Spanish is difficult.)
José se lo regala a él. (Jose gave it to him (i.e., someone else).
but:
*José se lo regala a sí mismo. (José gave it to himself.)
* Special rule for sí: When the third person subject (José in the above example) refers to himself, herself, or itself, Spanish adds the adjective mismo/a to clarify the object.