I asked this the other day. But I am asking again as I didn't get an answer. Suppose I want to make a small niche improvement on top of existing search engine

I asked this the other day. But I am asking again as I didn't get an answer. Suppose I want to make a small niche improvement on top of existing search engines. I want to them to provide first level results and then I will provide additional filters on top. For example, I would get the results from Bing for example, and then remove all websites which are ad supported. How should I go forward with this plan? Are there any APIs available? Or should I put on a biz dev hat and talk to Bing guys?