Personally, I'd go down the self-publishing track. Getting a novel accepted by a major publisher isn't easy, and the rewards are small either way.
If you do want to submit to a publisher, I know that Macmillan accepts unsolicited manuscripts through their website.
As for editing, it's a good idea to get someone to read what you've written and give you feedback, but when it comes to line editing, I find it useful to use text to speech on my computer, and sit there reading through it as I listen to my words being mangled by an electronic idiot.
It's a pain, but it works.