You're going to get a wide range of answers on this, Bryan, because different authors have different views on marketing. Many don't do a thing--relying on the publisher's selling power to do the work.
However, I'm probably the queen of marketing on my own dime on this forum. I think it's had a positive impact on sales, but marketing is so very subjective that I might only be deluding myself.
That said, I want to stress that any marketing I do is from my PROFITS on the book. I've already received an advance and am spending part of money in hand on increasing exposure to the public. So far, what I've done is:
1. Printed bookmarks.
2. Printed postcards.
3. Mailed said postcards to a large mailing list of authors in a similar genre.
4. Inserted 4-color advertising (from 1/4 page to a full page) in major print magazines in two genres.
5. Made packages of promo materials and send them to booksellers in other countries that don't often get stuff for first-run American titles.
6. Attended conferences and conventions to meet and greet.
7. Sent out dozens of ARCs (Advance Reading Copies) of the books to reviewers so reviews can be available when the book is released.
8. Prepared press releases about "news" related to the books and paid for extra distribution.
That's my list to date. It hasn't been cheap (over eight grand last year), but I really do think it's working. Good luck!
