A list of outstanding Strategy Guides that are just so well done they deserve to be on some kind of recommendation list.
If a game has had:
a re-release of some sort (a port or re-arrangement with notable added/removed content (Example: Super Mario Advance 3: Yoshi's Island))
an alternate version (through regions or systems) (Ex: The Lost Vikings Sega MD version vs SNES version)
Then please specify which version the guide is used for.
Reboots (Ex: Splatterhouse (2010)) and full-blown remakes (Ex: Ys: Oath in Felghana) should have their own entries separate from their original games.
If by some chance a guide can serve well enough or even entirely for an alternate version or release of a game, then please specify the systems and extents in the game guide's description, along with any other notes you see fit, especially regarding original printed releases (i.e. extra goodies like CDs, pinups, and other such rarities).
Dragon Warrior 3 (aka Dragon Quest 3 due to copyright issues) has a bigass world and an absolute fuckton of secrets to find, and this guide will help you track them all down. From the hidden goodies to the hard-to-reach Pachisi loot, no stone will be left unturned from your journey's end up to the last post-game challenge. It also tells the workings of the personality test at the beginning, which is essential to determine your Hero character's ideal stat growths. As expected, bestiary, items, and equipment are also included, but each also has artwork to go along with them, making for a nice visual feast. Spells are also noted in approximate level learned (due to DQ3's alternate spell-learning system from the series norm) and also their effects and range of damage/healing. In addition to the colorful map-filled walkthrough, there's also a handy checklist to help recall where you last left off and where to head next. One of Prima's best guides, and a handy aid to your quest. Translation differences aside, you can also use this for the Super Famicom (SNES) version of Dragon Quest 3, though the personality names and test results are harder to translation-match than the towns and items.
You thought you were rid of it? Think again. Anyone who even glanced through this shit-heap was scarred by it, and the rest are pained enough just by hearing stories of it. Nobody wants to remember it, but at the same time, we can't ever let ourselves forget it. Possibly the best example of how NOT to do a strategy guide. Released at the turn of the millennium, Square got the "brilliant" idea to make a bare-bones printed guide that largely contained key-codes to access the actual meat of it ONLINE-ONLY. Some speculate that this was to gain further supporters for their then-new playonline service, which lead into FF11, and might have ended up affecting FF10 (somehow). Whatever the reason, it lead to a bunch of well-deserved backlash; and, since then, it seems neither Square or anyone else has repeated this stupid mistake (or so we hope). The biggest hassle of this was that the dial-up internet connection was the then-standard and while broadband was technically a thing, it was both expensive and not offered in as many areas. Just imagine trying to find out how to save Blank and then suddenly someone decides to call and talk for hours and there's not a damn thing you can do about it. The best part of all this is that the actual webservice isn't even up anymore and SE's own mirror is a 404. You can find some user-made mirrors around the net, but hell, the guide wasn't even that great in the first place (Westerners "discovered" a "hidden" event years after it was actually noted in Japanese guides). So, honestly, just stick to the FF Wikia's guides or gamefaqs, for your own sake.