What is the difference between a published writer and an unpublished writer? Chance.
There are some writers out there who will brook no criticism and think that the publishing industry is against them. A website worth a read in that regard is 101 reasons to stop writing. It has only reached number 17 so far, but it's well worth a read. It's also funny.
Those of us who don't think we're perfect, but are unpublished, just haven't hit the G-Spot yet. We haven't sent the right book to the right agent at the right time. Chance has not come our way, but we don't stop trying.
How do we get chance on our side? Be in a position to take advantage of it when it does come. That means writing as much as possible, critiquing it, getting others to look at it and critique it and send it off. The more quality writing you send off, the more chances you have to take advantage of 'chance'.
The internet has opened many opportunities, such as blogging, which can help us write. There are also many eZines out there that are begging for content. Some even pay.
Electronic distribution is not expensive, which is why many eZines are free and relatively advert free. Many of them are also of a high quality with good and experienced editors in charge.
The more short stories you send off to these eZines, the more chance you have of being published. The more you have published, the more your query letter will stand out when you send your novel to an agent or publisher.
Even so, you will get rejected more often than accepted. It goes with the territory.
Google ezine and your genre and see what comes up. Give yourself more chances to get ahead of the crowd.