get referential values

Knowing only tablename (schema_name.table_name) how to retrieve foreign keys
and related values. (using pg_catalog is preferred). I developing framework
for adobe flex (on php and postgresql).
Already figured out how to get primary key, not null columns and column
types, but kinda stuck here.
I can post these queries, if someone needs (it would be nice to have these
in wiki - where I've seen the query for primary key retrieval).

I need following format:

select .... 'schema_name.table_name'::regclass....

no | fk_name| table_column_name | foreign_table_name | foreign_column_name

no is used for composite foreign keys.

Thanks!

Esmin.