Darksearch allows you to query cached onion sites, irc chatrooms, various pdfs, game chats, blackhat forums etc...

Darksearch also has an API in the works. Currently you can't scrape specific data for your queries, but you can retrieve metadata on your searches by using a GET request on darksearch.io/api/YOUR_QUERY/PAGE_NUMBER

$ curl -XGET darksearch.io/api/spies/1

{
  "duration": "0.038", 
  "query": "spies", 
  "size": "36", 
  "total_pages": "4"
}

The Darksearch index is growing as more scrapers get built...