Henry VIII's great seal
Charles Cruickshank's 'Army Royal' or 'Henry VIII's invasion of France' depending which publishing you can get hold of is perhaps the most in depth single source, after that from a gamers perspective there is then the Osprey men at arms 'Henry VIII's Army'.
Whilst these are good, particularly the former, I've learned to use them as a guide, articles which can set the scene and give you a feel for the subject but not as absolute sources, for that you've got to go to the original documents and this campaign is perhaps one of the first in English history where a great deal of such items have survived and not only that, they've been catalogued, transcribed and archived and you can view them online, for no charge, here;
Letters & Papers, foreign & domestic
Here you'll find day by day accounts, building up the bigger picture of the campaign as it happened, preparations, nobles and their retinues, pay, equipment, troop numbers, mercenaries, details of engagements with the enemy, diplomacy and so on.
They're written in old English so it's not bed time reading but you can very easily get the pieces of information that you need. Not long after I discovered this source I found myself questioning quite a lot of what I'd read and understood about Henry's army at this time as well as realising perhaps why this army is ignored or just treated as a facsimile of the force which fought at Flodden.
One of the first things I did was to re-write the army list I was using as it meant almost nothing, it felt as though it was written based upon assumption and guesswork - this wasn't a medieval bow and bill army, there were much greater elements to it; the intrigue was that an English renaissance force had never previously been assembled or tested in this manner - i began to draw parallels with the armies of Charles the Bold - this was very much a force of combined arms; bow, bill, pike, shot, artillery,light medium and heavy cavalry, a veritable chess set on paper and a formidable one at that; imagine facing a body of men which can employ artillery, gall you with bow shot, disrupting your formation, then punch you with their own shot, then the tips of their pikes before the bills rush in and cut you to pieces and the cavalry finish the job, it's almost perfect.
The Battle of the Spurs, though known as a cavalry engagement began with longbowmen and light guns disrupting the french gendarmes creating a clear path for the Kings Spears to rush and scatter them to such an extent that they shed armour to better enable their retreat.
I think the real intrigue is that this army was not tested in pitched battle - which is where the hobby comes in - is the fact that there are no comparisons or reference points an issue for the gamer?
Charles' experiments failed him for various reasons and you can see some of these being repeated here, particularly where mercenaries are involved; - the English and their Landsknecht allies just didn't get on and the Burgundian cavalry only joined in the fray where it was absolutely clear that the immediate danger was over. Moreover the skirmishes that 'worked' appeared to be where the English were working together so it's interesting to think how one might replicate that on the gaming table.
This army intrigues me many times over.