You need the list because the story is one continuous narrative. Think of it like a very long TV season. You wouldn't watch episodes out of order. 'Vector Prime' is the premiere. 'The Unifying Force' is the finale. Everything in between is the season arc. The list is your episode guide. Some episodes ('Traitor') are critically acclaimed. Others are more like filler. But they all build the world and the conflict. So, find a reliable source for the list—Wookieepedia is perfect. Then, settle in. It's a unique experience in the Star Wars universe, one that takes its time and isn't afraid to get dark. The list is your ticket. Use it.
Interesting you ask about the 'book list' specifically. Some reading lists include essential predecessors like 'I, Jedi' or the 'Corellian Trilogy' for Han/Leia family context, and the 'Young Jedi Knights' series for the kids. But the NJO series itself is a linear list. It doesn't branch. So its fit in the timeline is a straight line. You read 'Vector Prime' then 'Dark Tide' etc., all the way to 'The Unifying Force.' That's 25–29 ABY. Then you move on.
For a series this long, character charts can help more than a simple list. The 'correct' order is the one that lets you follow Jacen's transformation, Jaina's hardening, Luke's burden of leadership, and Mara's struggle. If you feel lost on a character's motivation, you might have missed a book where they had a pivotal scene.
Use the publication order as your backbone, but maybe keep a notepad on the side tracking major character moments. It helps you see why the order is so important—the character arcs are the true through-line, and they're meticulously paced across all nineteen volumes.
I have a spreadsheet, okay? A literal spreadsheet. NJO occupies cells ABY 25 through 29. It comes immediately after the 'Hand of Thrawn' duology (which is ABY 19) and the novel 'Survivor's Quest'. There's a bit of a time jump in-universe between 'Hand of Thrawn' and 'Vector Prime', a period of relative peace. So in a pure chronological book order, you'd read 'Survivor's Quest', then jump to 'Vector Prime'. That's the cleanest narrative handoff.
This is a classic case of needing to define what you mean by 'book list.' If you mean the narrative sequence of the New Jedi Order, it's standardized. But if you're talking about the physical or digital products you can buy, absolutely there are differences. Some European editions omitted the short-story collections like 'Vector Prime' and instead integrated those stories differently? I'm not 100% sure, but I recall forum chatter about Italian editions having a different structure. For the average English-language reader sticking to major publishers, you won't encounter this.
Honestly, just go by publication order. It's designed to be read that way. 'Vector Prime' is book one, and it sets off the whole cataclysm. Trying to piece together some 'true' chronological order by mixing in all the short fiction and junior novels is a recipe for burnout before you even hit the halfway point. The main narrative flow is contained in those nineteen Del Rey novels. I tried getting fancy with a combined timeline my first attempt and gave up in confusion. My second attempt, I just read the big books one after another, and it was a vastly better experience. The story feels paced correctly that way.