Looking for tips on how to outbound SMB owners to try and acquire their business

If anyone has any advice on how to effectively outbound SMB owners to try and acquire their business then please share!

Below are just some questions that I have but any tips on this topic are welcomed:

- Are there any good books, blogs, etc. on the subject?
- I'm partial to Apollo.io for this kind of work but let me know if you recommend a different tool?
- I believe those who employ this strategy use SIC codes is that right? How are they using them?