Is there a parser for Postgres' auto_explain to make it easier to read and understand?
SUGGESTION #1
If you are just looking to take an EXPLAIN plan and instantly present it, here is a SQL-Fiddle like site called explain.depesz.com. Just copy-and-paste the explain and hit Submit.
SUGGESTION #2
You could try pgAdminIII which comes with Graphical Explains
See the following links to how to use pgAdmin and other methods

PostgreSQL : Up and Running (Chapter ob pgAdmin)
PostgreSQL Wiki's Using EXPLAIN
READING PGADMIN GRAPHICAL EXPLAIN PLANS
pgAdmin 1.4 online documentation