A long while back, I had the Prima Games Strategy Guide guide for FR/LG and I found it again the last time I was at my parents' house and had a flick through.
It's a work of art. I'm going to have to do a longer/more indepth post on it at some point because it's just so hilariously amateurish, in the manner of a lot of tie-in books and strategy guides.
There's a lot that's good about it - the book includes a full Pokedex for the first 251 Pokemon, telling you what moves they learn, where to find them, and how to evolve them (for a lot of the Johto species, it's just "trade from Colosseum", or "trade [species] from Colosseum, then breed") - but the walkthrough just stops dead after Three Island and doesn't cover anything after beating the Elite Four, and contains a lot of incorrect information, like Kingdra evolving from Seadra with a Water Stone or the player being able to use Surf after beating Misty.
One of the things that's most funny to me, though, is that whoever wrote it had evident difficulty working out what Pokemon the rival uses. Whenever you fight the rival, they'd do a short section on how to beat him and display his team in the following format:
EVERYONE FIGHTS:
- [pokemon]
- [pokemon]
- [pokemon]
AND IF YOU PICKED:
- Bulbasaur (add [pokemon], [pokemon], and [pokemon])
- Charmander (add [pokemon], [pokemon], and [pokemon])
- Squirtle (add [pokemon], [pokemon], and [pokemon])
The thing is, they just couldn't seem to make it work. Not only would they often have the wrong Pokemon, like Arcanine or Gyarados, in "everyone fights", in the "and if you picked" section they'd often include more than one starter, double up on types, and sometimes only include two Pokemon. So you had funny stuff like "if you picked Squirtle, add Blastoise, Exeggutor, and Venusaur", or "if you picked Charmander, add Blastoise and Arcanine".
Overall, it's not a bad guide, and gets the majority of stuff pretty right. But it's the little clueless touches that make it memorable for me.