Go big — content 50 self - publishing authors in your genre who are doing decent (in the top 50K or so on Amazon) and
ask if they want to do a group sale,
everyone prices at 99cents
for one day, and
everyone promotes the discount... link to one page (probably on your site, or a bigger blog) listing all 50 authors (or every author can
copy / paste your post on their own page, listing the 50 authors, links to the amazon page, and links to their blog posts.