Moving to Alaska would be a good start…

There are agencies like this that round up crews, but you should start by reading this.

Jobs on fishing boats are highly sought after. Most people start out by working the ‘slime line’ in the processing plants (or large Tender ships that do processing at fishing sites). From there you’ll get to know other fisherman, captains, etc.

Sadly, usually it’s a case of ‘who you know’ that gets you on board.