"Guerrilla Marketing" was coined by Jay Conrad Levinson in his popular 1984 book (with the same name), as an unconventional system of promotions on a very low budget, by relying on time, energy and imagination instead of big marketing budgets.

Like his books, his web site encourages and promotes creative marketing. There are some features (teleclasses, coaching) that require joining up for a fee but there are dozens of scores free articles along with a newsletter you can subscribe to.

Not a site limited to the marketing of books, this general marketing resource pushes "out of the box" thinking and may provide the inspiration you need.