Yeah, I think A Confederacy of Dunces is probably the perfect New Orleans book.
If you find yourself imitating another writer, that doesn't have to be a bad thing, especially if you are a young or a new writer. However, you should be conscious of exactly how you are imitating him - word choice, sentence structure, motifs? - and think about why you're doing it.
I'm your nightmare. Did you think you were done with nightmares, now you've become one?
And I can't think of a reason I'd ever use a pseudonym, as I wouldn't want to publish something that I didn't like enough to put my name on it.
I don't think it is possible to give tips for finding one's voice; it's one of those things for which there aren't really any tricks or shortcuts, or even any advice that necessarily translates from writer to writer. All I can tell you is to write as much as possible.