Why you would want an agent:
Agents get you in the door at the big 5 publishing houses. Most of the big publishers will only take query letters from agents. If you are a published author already with a house, the main reason you would want an agent is to ‘trade up.’ i.e. – move from a smaller publisher to Penguin.
Time from sale to bookstore with a traditional publisher:
Usually 12 months to 18 months. 15 months is typical.
Deadlines:
Miss your deadline with a traditional publisher, and you are toast. This means deadlines for getting back on publisher edits too. Production time in factories is booked long in advance. If your book isn’t ready to go on the line in its slotted time, then your publisher loses money. Say goodbye to your next sale.
Print on demand publishers:
Some smaller traditional publishers have let go of production runs and are now using print on demand technology via Createspace. Usually this means shorter time from sale to bookstore. (i.e. a book sold to a publisher in March might be for sale by June.)
How bookstores work:
Bookstores typically buy books from the publisher or distributor at 60% of cover. So the bookstore makes 40% (less shipping costs). Usually the shipping costs are born by the retailer, but sometimes publishers will have specials.
BUT – if a book doesn’t sell, the retailer can rip off the cover, send it back to the publisher and get a refund. The books are then destroyed. (Yes, it’s appalling. It all has to do with shipping costs. Not worth it to ship books back.)
Problem – this doesn’t work with print on demand books. You can’t return anything to Createspace. So retailers are reluctant to order books that are not from traditional publishers using the traditional print-run method.
How long is your book on a shelf:
In a store like Chapters (the Canadian big-box equivalent of Barnes & Noble), if your book doesn’t sell in 45 days, they usually remove it. Gone forever from the shelves, unless you become a NYT bestseller in the future, and they bring back your backlist. Yes, this is unbelievably short. It used to be 6 months. The book business is brutal.
I think the third word in that last line is the key. The book business is a business. It’s there to make a profit for shareholders. We are in love with our products, so we find that hard to face. Recently, I saw a study that said approximately 40% of writers are manic-depressive.
The rest of us just drink.

Called the “Queen of Comedy" by the Toronto Sun, Melodie Campbell has connections in low places. Don’t dig too deep. You might find cement shoes.
Melodie has shared a literary shortlist with Margaret Atwood, and was recently seen lurking on the Amazon Top 50 Bestseller list between Tom Clancy and Nora Roberts.
Melodie has won the Derringer, the Arthur Ellis, and eight more awards for crime fiction. She didn’t even steal them. Worst Date Ever is her 12th book.