The best alternatives to Effect International are Clearbit, The Org, and Miner by Automata. If these 3 options don't work for you, we've listed a few more alternatives below.
Miner is a (free) search engine that only delivers search results from company websites. Research your total addressable market, find new customers, and keep tabs on competitors with ranked search results that only depend on the relevance of text on the page.
ListChirp is a data science company offering APIs and flat files for customer intelligence. Use our products and associated database of 1.2 billion unique person records to build enriched or new person profiles into your apps, products, and tools.