Napoleonic Armies by Ray Johnson is a reference book detailing those armies to a level useful for miniature or board wargaming. It is divided by country with many of the smaller German kingdoms also detailed.

For each country there is an introductory section then their military organization in 1805 and then each year up to 1815. Many countries have gaps or only a few years due to being amalgamated/created/destroyed during that time period.

The yearly overview is usually type and number of regiments/battalions (sometimes divisions and corps are listed for countries that had them). Then infantry, cavalry and artillery sections to discuss organization at battalion/company levels. Lowest level is how many men in each company and gun type/number of guns in artillery batteries.

This is a semi-scholarly work. Writing style is ok. The reader is expected to know Napoleonic military history. Battle are named but not described. Events of the year may be referenced but not detailed. Politics are rarely discussed.

Layout is not great but acceptable. Obviously edited since I didn't spot any spelling or grammatical errors. But spacing could have been better, tables might have helped, making sure information doesn't split over from even to odd page (so you have to turn the page to compare) would have been nice.

Still, this is a cool book to have even though it's over three decades old. Probably a bit out of date but the level of description is high enough that it's unlikely to have many corrections (due to new research over the last three decades).