This query; 
select * from pg_tables;

Produces this output. pg_tables is a standard view defined on one of the system tables.
I think the tables associated with the 'public' schema are what you want.

     schemaname     |        tablename        | tableowner | tablespace | hasindexes | hasrules | hastriggers
--------------------+-------------------------+------------+------------+------------+----------+-------------
 information_schema | sql_features            | postgres   |            | f          | f        | f
 information_schema | sql_implementation_info | postgres   |            | f          | f        | f
 information_schema | sql_languages           | postgres   |            | f          | f        | f
 information_schema | sql_packages            | postgres   |            | f          | f        | f
 information_schema | sql_sizing              | postgres   |            | f          | f        | f
 information_schema | sql_sizing_profiles     | postgres   |            | f          | f        | f
 pg_catalog         | pg_authid               | postgres   | pg_global  | t          | f        | t
 pg_catalog         | pg_statistic            | postgres   |            | t          | f        | f
 pg_catalog         | pg_type                 | postgres   |            | t          | f        | f
 pg_catalog         | pg_attribute            | postgres   |            | t          | f        | f
 pg_catalog         | pg_class                | postgres   |            | t          | f        | f
 pg_catalog         | pg_autovacuum           | postgres   |            | t          | f        | f
 pg_catalog         | pg_inherits             | postgres   |            | t          | f        | f
 pg_catalog         | pg_index                | postgres   |            | t          | f        | f
 pg_catalog         | pg_operator             | postgres   |            | t          | f        | f
 pg_catalog         | pg_opclass              | postgres   |            | t          | f        | f
 pg_catalog         | pg_am                   | postgres   |            | t          | f        | f
 pg_catalog         | pg_amop                 | postgres   |            | t          | f        | f
 pg_catalog         | pg_amproc               | postgres   |            | t          | f        | f
 pg_catalog         | pg_language             | postgres   |            | t          | f        | f
 pg_catalog         | pg_largeobject          | postgres   |            | t          | f        | f
 pg_catalog         | pg_aggregate            | postgres   |            | t          | f        | f
 pg_catalog         | pg_trigger              | postgres   |            | t          | f        | f
 pg_catalog         | pg_listener             | postgres   |            | f          | f        | f
 pg_catalog         | pg_cast                 | postgres   |            | t          | f        | f
 pg_catalog         | pg_namespace            | postgres   |            | t          | f        | f
 pg_catalog         | pg_conversion           | postgres   |            | t          | f        | f
 pg_catalog         | pg_depend               | postgres   |            | t          | f        | f
 pg_catalog         | pg_tablespace           | postgres   | pg_global  | t          | f        | f
 pg_catalog         | pg_pltemplate           | postgres   | pg_global  | t          | f        | f
 pg_catalog         | pg_shdepend             | postgres   | pg_global  | t          | f        | f
 pg_catalog         | pg_auth_members         | postgres   | pg_global  | t          | f        | t
 pg_catalog         | pg_attrdef              | postgres   |            | t          | f        | f
 pg_catalog         | pg_constraint           | postgres   |            | t          | f        | f
 pg_catalog         | pg_database             | postgres   | pg_global  | t          | f        | t
 pg_catalog         | pg_description          | postgres   |            | t          | f        | f
 pg_catalog         | pg_proc                 | postgres   |            | t          | f        | f
 pg_catalog         | pg_rewrite              | postgres   |            | t          | f        | f
 public             | attachment              | trac       |            | t          | f        | f
 public             | auth_cookie             | trac       |            | t          | f        | f
 public             | component               | trac       |            | t          | f        | f
 public             | enum                    | trac       |            | t          | f        | f
 public             | milestone               | trac       |            | t          | f        | f
 public             | node_change             | trac       |            | t          | f        | f
 public             | permission              | trac       |            | t          | f        | f
 public             | report                  | trac       |            | t          | f        | f
 public             | revision                | trac       |            | t          | f        | f
 public             | session_attribute       | trac       |            | t          | f        | f
 public             | session                 | trac       |            | t          | f        | f
 public             | system                  | trac       |            | t          | f        | f
 public             | ticket_change           | trac       |            | t          | f        | f
 public             | ticket_custom           | trac       |            | t          | f        | f
 public             | ticket                  | trac       |            | t          | f        | f
 public             | version                 | trac       |            | t          | f        | f
 public             | wiki                    | trac       |            | t          | f        | f
 public             | bugs                    | tjb        |            | t          | f        | t
 public             | parts                   | tjb        |            | t          | f        | t
(57 rows)