You should be able to just run select * from information_schema.tables to get a listing of every table being managed by Postgres for a particular database.

You can also add a where table_schema = 'information_schema' to see just the tables in the information schema.

 

The view pg_tables provides access to useful information about each table in the database.

pg_tables

 Columns

Name	Type	References	Description
schemaname	name	.nspname	Name of schema containing table
tablename	name	.relname	Name of table
tableowner	name	.rolname	Name of table's owner
tablespace	name	.spcname	Name of tablespace containing table (null if default for database)
hasindexes	boolean	.relhasindex	True if table has (or recently had) any indexes
hasrules	boolean	.relhasrules	True if table has (or once had) rules
hastriggers	boolean	.relhastriggers	True if table has (or once had) triggers