I don't recommend any message boards any longer for a first timer. The information is all over the place so it's hard for a first timer to use to plan.
I do recommend 2 books - The Unofficial Guide or The Passporter Guide. It depends on how much of a reader the person is for me to decide which one to recommend.
That way they get quite a bit of the basics.
But the books aren't 100% accurate either with the whole magic band, FP+ stuff being such a moving target right now.
Oh well, we all do the best we can and hope the trip turns out well.