We are both writers here - I haven't even finished my first Magnum Opus.
Publishing is difficult - unles you are an 'accepted' author - on board already - most publishing houses won't give you much more than a cursory look - that is - if you can find one for your genre.
The Boss went to a forum recently, and the advice was that 'anything with numbers and secrets or whatever is a good starter'. The Da Vinci CODE (bleep, bleep, bleep)... The SIXTH Sense, The Bourne CONSPIRACY etc, etc.
Often the advice is 'self-publish' - which you can find some very reasonable sites for doing - or by having an internet site of your own.....
(a certain googling company are offering these free for business for twelve months followed by a very reasonable fee monthly). We know one young guy who has set up such a site.
Good luck - now, Igor - how's that damned book going? How much longer, slave? Keep it up and you WILL be a GHOST writer (hmmm - not a bad title grab there).....