What is your go-to way to get enchanted items?

Depends on the version of the game. In older versions, I think you could choose what enchantment you want from enchanting tables and retry until you find the right one; I believe now, you have to use Lapis Lazuli and you're stuck with the options given to you. But in later versions, enchanted books are handy, especially for crafting higher tiers; I generally save the books for rarer items like a Diamond Sword. But for iron items, it's better to use an enchantment table for a low tier and then use an anvil to combine something like Protection I armor with another Protection I armor for Protection II since it's pretty easy to farm for iron.

And I think it's relatively quick to craft full iron armor all with Protection II, convenient to add Feather Falling on boots (if you're exploring a lot, especially in ravines), and useful to have Sharpness III on a Diamond Sword and Power II/Fire Aspect on a Bow.

 

You can find excellent enchantment books with fair prices in villages. Still, I prefer to enchant them myself on the enchantment table.

 

I generally don't bother with villages, because most of the time the offers aren't that great and sometimes you have to find your own emeralds to exchange for books. Personally I just collect books I find in the End and farm a bunch of experience from Quartz farming at the Nether to enhance books.

 

First I enchant the fishing rod and collect enchament books for others by fishing

 

Fishing has terrible odds (from a 5% chance of even catching treasure, you only have a 0.8% chance of actually obtaining an Enchanted Book). You'd have better odds exploring dungeons, where chests have about a 15% chance of containing an enchanted book. And you also gain a lot of other things from exploring underground, like ores and experience.

I don't know anyone who's tried to fish enchanted books, especially in competitive minigames like Ultra Hardcore. It's too time consuming, and you'd be making less progress.