Getting into the nuts and bolts now.

Your draw length is likely to be a solid inch shorter with a longbow than your compound, if not 2". Grip styles aren't very different any more. Most people use the same low wrist grip and soft elbow for compounds that we use for shooting longbows. What makes the difference is, you tend to stretch into the draw length with the let-off on a compound but with a longbow you've got the full draw weight at anchor. That compresses the joints and doesn't let you stretch out like you can with the compound.

So, figure on drawing about 27" with a longbow.

Longbows vary. Some like heavier arrows than others. Shoot 'em with an unweighted carbon and they'll rattle your teeth. Some do just fine with light arrows. I'd imagine you're not quite ready to make the leap all the way to wood arrows yet, and you'll want to stick with carbon for the durability - you ARE going to miss quite a bit at first.

So, for a starter arrow I'd be looking at the Carbon Express Rebel, which I think is just the old Terminator with a new name. Good weight and excellent durability. Size 4560.