I am trying to figure out what spine wood arrow to get for my 65lb @ 28 longbow. I remember reading somewhere that I would need a heavier spine than 60/65 or 65/70. I am actually drawing the bow about 29" so its more like 68lbs. Can someone point me in the right direction?

How long are your shafts?

How long is your draw length?

What weight of field point/broadheads do you intend to use?

How heavy do you want the finished arrow to be?  How efficient is the design of your bow (D shape? heavily R/D ?)?

What arrow velocity would be acceptable to you?

To add to flatbow's...what is the centershot?

To me, woods are like all the other arrow materials: there will be some trial and error for each individual archer because there are simply too many variables.

To give you a starting point: if you are using 30 inch long arrows with a 125 grain broadhead, I would start with 80-85 and go from there. Gary

Oops!  I missed where you'd mentioned draw length.  I'll mention my POC setup and it might help. First off, I have 2 longbows - one is a high efficiency bow that is 74# @ 28" and the other is an extremely high efficiency bow that is 61# @ 28".  My drqw length is righ at 28" and shooting the same arrow, the 2 bows fling any give arrow at virtually the same speed.  What I'm finding that a POC shaft cut to 29" with a 190 grain field point flies very nicely from both of these bows.  Finished weight comes in around 610-620 grains.  I'm getting an arrow velocity around 165 fps.

EDIT:  I forgot to mention that my shafts are spined at 85-90 (though I could also get away with 80-85s)

I use 65-70 tapered cedar shafts for both my recurve and longbows that pull 65#. I also use 160gr Snuffers

just for a comparison, I shoot 62@27 with a 28 in POC and a 135 gr head and use 80-85 cedars.. out of a longbow not quite cut to center using fast flite string