http://www.w3schools.com/sql/sql_insert_into_select.asp
Don't fully understand what you're trying to do, but maybe something like:
Code:
INSERT INTO goallists (listid, entry)
SELECT 350, npc_types.id FROM npc_types
JOIN spawnentry ON npc_types.id = spawnentry.npcID
JOIN spawn2 ON spawnentry.spawngroupID = spawn2.spawngroupID
WHERE zone = 'warrens' AND race = 455 AND name NOT LIKE '#%'