You go into a bookstore and check the inside front page of books similar to your own, then look up the house websites to check their guidelines.
Most houses will only take agented submissions, though.
So you write down the names of the authors of those books, check their websites and see if they mention their agent. If not, then a short polite letter asking who reps for them is okay. (Dear __ I'm an aspiring writer in need of an agent and hoped you might share the name of your representative.)
Being a first time author, what should I avoid when looking for a publisher?
EVERY house or agent that charges ANY kind of fee. Agents get paid
after they sell your work. Houses pay YOU.
Also, how can I avoid signing a contract with a House Publisher who accepts my book but does nothing to promote it?
Sometimes this is unavoidable. Most houses have top selling writers they put most of their promotion behind, then what's left goes to the rest of the writers.
This is still more than you would ever get from a scam operation like Publish America--and stay away from them, by the way. They are a publishing tar pit. Books go in and are never heard from again.
Legit houses have DISTRIBUTION. Your book is listed in their ordering catalog and that's what gets it into the stores and libraries, which is what you want. If your work shows promise it might get listed in their big ad in Publisher's Weekly or some other magazine. They usually do some kind of promotion for new releases in hopes it will "click."
Just don't expect them to take out a full page ad for a first novel unless you've got cover blurbs from a dozen bestselling writers in your genre.
And it is not about selling
one book; it is about selling all those to follow.
The submission process is SLOW. I was on the fast track with my first novel and it took two years to sell. (Every time it came back I did a rewrite!)
To keep your head from exploding be working on and
finishing your next 2-3 books.
Better believe if an agent takes you on she is going to want more than one title to shop!
One of my friends closed a three book deal for her romantic suspense series, landing a (RARE) six-figure contract.
She is an outstanding writer, which helped. The other help was that all three books were finished, polished, workshopped, and beta-read within an inch of their lives. She finished them while shopping the first one around.
I landed a multi-book deal the first time out the gate because I'd finished books 2 & 3 and had begun the 4th while in the submission process. They knew I wasn't a 1-trick pony and was serious about having a career.
Good luck!