The Grandmother Earth writing contest has a lot of prizes to offer writers. There are two main categories -- poetry and prose -- with a $150 first prize for each category, as well as second and third place cash prizes (and a fourth place prize, for the poetry contest). The entry fees are only $10 for up to three entries, and $2 for each one after that.
In addition to the two main categories, there are additional awards that will be handed out, including "Best use of humor" and "Best haiku." There's no additional fee to be considered for these awards (just mark it on your entry) and for each one there will be a first, second, and third prize of $50, $25, and $15, respectively.
There are many chances to win with this contest, and you can even enter previously published poetry or prose. The postmark deadline for submissions is August 1st.