Alright, there's a lot to try and answer here and I'll do so to the best of my ability - this is my first time responding here so I'll do my best! :)

The Golden Age of Piracy is typically dated approximately 1650-1720 (if you do more in-depth research, the exact dates will slightly differ). This is the general timeframe when pirates were the most active and hosted a variety of notorious pirates such as Blackbeard, Captain Kidd, and Henry Morgan.

Piracy studies are a relatively young field and has been steadily developing, but as a result, there is still plenty of discourse to be had about the roles pirates played in various transatlantic economies (resources and trade, slavery, etc.) and the larger motivations of these pirates. What was the nature of their violence? Individual motivations varied wildly from one account to another, ranging from impoverished working class men seeking wealth to others seeking political favor prior to the larger crackdown on piracy (which had begun in the later 1690s - piracy had flourished from around 1605 to 1696 and yet the most notorious pirates we remember in popular culture emerged afterward!).

I wish I could answer more of your questions - despite having taken a seminar on the subject, I wrote my final paper on an aspect of piracy (executions and public opinion, which I'll gladly provide information about if you want) unrelated to your specific questions. However, I can help point you in the direction of some sources (which, unfortunately, I have since gotten rid of since I took the class, so I no longer have access to them myself).

Authors such as Robert Ritchie (I read his book Captain Kidd and the War Against the Pirates) take on a more sympathetic view of pirates and their motivations. Pirate Nests and the Rise of the British Empire, 1570-1740 by Mark Hanna and Buccaneers of the Caribbean: How Piracy Forged an Empire by Jon Latimer served as great (but VERY densely-written) resources concerning many of the political and economic motivations and aspects of piracy from the perspective of the pirates themselves and the empires they served. Of course, all sources have their limitations and biases, and Latimer wrote strongly in favor of Britain and perhaps doesn't credit Spain's influence in the transatlantic world nearly enough, but his work overall served as a well-researched and in-depth look at Caribbean piracy in the grand scheme of things in the Atlantic world from empire-building to war efforts and to the slave trade. Another source I highly recommend is a collection of essays found in The Golden Age of Piracy: The Rise, Fall, and Enduring Popularity of Pirates put together by David Head - the compilation addresses specific colonial, economic, and political motivations as well as the ongoing legacy of pirates and their actions in what I found to be an engaging read!

The political aspects of piracy will help answer your question on the origins of these boats - while some were stolen in ambushes and raids, many pirates were given their first boats by their empires in exchange for bringing goods back to the crown - there's plenty to be read up on the similarities and differences between pirates, privateers, and buccaneers, something that I do not claim to have enough knowledge about to make a hard-line distinction. Blackbeard, for example, is speculated to have served as a privateer in Queen Anne's War before turning to piracy - privateering for empires was falling out of fashion and these former privateers needed to make a living with their skills somehow (one of Ritchie's big arguments: pirates were often slaves to the larger economic structures of the transatlantic world). But this again assumes universal motivations for piracy, which in reality were much more varied (but tended to have strong economic ties).

Goodness this got much longer than I anticipated when I started this and I really hope what I've put together is helpful to some degree. This is a tough field to get involved with because of how new it is and the vastly different interpretations of pirates' motivations and roles - it was a real headache when I was studying it all for the first time. But I hope I've got you pointed in a direction and that I've helped out some. :)