After linking one of my players to this site, he was interested enough to have a poke around, and decided he wanted to try some D&D 3.5e. However, to keep the heroic fantasy style, he wants to play E6, and has convinced the rest of us to try it out. Since we are all new to WotC-era D&D, and are only going to have characters up to level 6 + some extra feats, what sourcebooks are most useful (in terms of how much content we could use), apart from obviously the Player's Handbook, Dungeon Master's Guide and Monstrous Manual?
The best few books for a good first game
There’s definitely something to be said for keeping to core, since it keeps the options limited to only a small set of classes and options.
Unfortunately, core has a lot of design problems, which makes its actual material very poor, in my opinion, for new players. Specifically, there are a large number of “trap” options: things that might, to a new player, sound good on paper, but don’t work well in practice. For a group new to the game, evaluating each option is very difficult, which can lead to very uneven experiences.
For example, the druid class is very powerful; it has powerful spells and can turn into powerful creatures, and gets another powerful creature as a sidekick. Not every new druid player uses those abilities to their full potential, but many do use them quite well (does a wolf sound like a good sidekick? does turning into a bear sound like a good idea? turns out, they are!).
Meanwhile, the fighter class gets a series of bonus feats. Several of these feats are quite good (though not as good as the druid’s spells), but a lot of the feats – most of the feats – are quite poor. A fighter who chooses good feats can keep up with a druid who isn’t maximizing his potential. But a fighter who chooses poor feats can find it very difficult to keep up even with the druid’s sidekick.
This reality has been acknowledged, in hindsight, by Wizards of the Coast. One designer even claimed (though I suspect it was merely an attempt to save face) that it was intentional, since they wanted to reward system mastery as that paradigm worked very well for Magic: The Gathering. As Wizards learned the system better, they designed better, more consistent material.
As a result, as much as it is good to try to reduce the complexity of the game for new players by limiting options, the specific set of options presented in core present very difficult choices. I therefore try to recommend that players start with some better-designed classes, even though they come from supplements.
Tome of Battle
My number one suggestion, in terms of books to buy, is Tome of Battle. The system presented therein is not complicated – it’s simpler than the core rules for spells – but more importantly the options within that system are more consistent than in core. Unlike feats, some of which are good and many of which are bad, with the maneuvers in Tome of Battle, you can just pick what sounds cool – it will be! And that’s excellent.
Between the three classes in Tome of Battle (crusader, swordsage, and warblade), you can easily create characters conceptually similar to those you would make with the barbarian (crusader or warblade), cleric (crusader), fighter (warblade), paladin (crusader), monk (swordsage), and rogue (swordsage) classes from core.
Because three classes easily cover the conceptual space of six core classes, Tome of Battle actually simplifies things. I cannot stress enough how much simpler and more consistent characters are when made from these classes rather than their core counterparts.
Complete Arcane and/or Dragon Magic
For those looking for magic, Complete Arcane presents the warlock: extremely simple to play, and less overpowered than the core spellcasting classes. The dragonfire adept from Dragon Magic is similar. Both come highly recommended for new players.
Gaps in this set
The biggest problem with this set of classes is the healing of status conditions, a major focus of the core divine magic. The crusader gets very good HP-healing abilities, but nothing (until very high level) that correspond to restoration, remove curse, break enchantment, or similar. Unfortunately, there is no real simple class that provides these; for those your best bet is still the cleric. However, 3.5 really does not require a heal-bot type, and a DM can either carefully choose his enemies to avoid permanent versions of these things or else provide quests to get potions, scrolls, wands, or aid from NPC spellcasters.
Nothing from these closely approximates either the bard or druid. The druid does have a very well-designed analogue in the totemist, but Magic of Incarnum is quite possibly the most difficult-to-learn book in 3.5, since its organization is quite poor (the system itself is actually excellent, and not particularly complicated; it’s just the explanation that’s complicated). The bard is largely unique. That said, the bard is also a pretty solid character; his spells are quite useful, without the extreme power of the core “full spellcasters,” and Inspire Courage is a very nice buff. So you could just play the bard if that’s your interest. He’ll be a little more complicated than the above, but not too bad.
Padding out your library
Of course, keeping your options limited to simple, good stuff isn’t the only goal a new group may have for buying books. Eventually, you’ll probably want more material, even if it isn’t particularly newbie-friendly. But there are a lot of books, so you want to make sure you spend your money efficiently.
In terms of getting the most “bang for your buck” for a new group looking to improve their library, nothing beats Magic Item Compendium. Everyone uses magic items, and the book’s got a lot of them. It’s also quite well organized for finding them, so even though there’s a ton of stuff, it’s not too bad finding useful items (unfortunately, nothing will make the careful gp-by-gp accounting of wealth in 3.5 not a headache, but MIC helps). If you do go with traditional spellcasters rather than the warlock, Spell Compendium provides a similar function, and as a bonus, those spells are often better-balanced than the core ones.
Beyond those, it depends a lot on preference. The “outside” books (Cityscape, Dungeonscape, Frostburn, Sandstorm, Stormwrack, also known as “It’s Crowded/Not/Cold/Hot/Wet Outside,” respectively) are very useful for campaigns set in the corresponding environments. If you’re interested in any of the official campaign settings, the “Campaign Setting” book (Eberron Campaign Setting, Forgotten Realms Campaign Setting, etc.) are musts, of course. And the various player-option books (various Complete X, Races of Y, assorted others like Tome of Magic or Magic of Incarnum) or DM-option books (extra Monster Manuals, books about various monster types like Lords of Madness or the Fiendish Codices, etc.) are mostly based on what sounds interesting to you (if you must have my recommendation, it’s Complete Champion first).
E6 is normally pared down and simple - so you might be best served keeping it to the core rulebooks or SRD material. A lot of the rules that cause issues in 3.5 come from sources outside of the core materials and in a campaign limited in power levels you really won't need much else, baring anyone who really wants to play a specific class or role not covered in the PHB