Ads on Askwritefish.  I try to screen ads on askwritefish and present only quality products and services.  Amazon allows you some freedom in choosing specific ads.   I try to choose Amazon ads based on books and products I have used, or read, or I have some knowledge about.  In addition, I read the customer reviews.  For example, all writing software I've researched (as shown on this page) has customers who love it and those who don't.  I encourage you to read the reviews before purchasing.

However, Google bases their ads on website keywords, so I have little knowledge of the product or service.  While the fishing ads seem pretty good (I've checked several), I try to manipulate the keywords so that no ads appear regarding writing, publishing, or obtaining agents.  I try to exclude those Google ads from my web pages.  I know of at least one ad that appeared (before I removed it) for a "literary agency" that appeared as "strongly not recommended" on the excellent website for writers -- Predators and Editors.  Of course, only a few of the google ads direct you to bad writing deals.  The rest are pretty good.  Just use appropriate caution.