Well, it may also help to know if you want 3.0 or 3.5 prestige classes.
In the 3.5 Dungeon Master's Guide there's the Duelist for swashbuckler-type fighters. The Dwarven Defender is restricted to lawful alignments I think, but that's the only other core PrC for purely nonmagical warrior-types.
Other possible prestige classes, from 3.0 though (I dunno if/where they're reprinted in 3.5, in most cases; I do know that several of these were reprinted in the DMG, Complete Warrior, or Complete Adventurer), there's all kinds of stuff in Sword & Fist (appropriate non-lawful ones include the Duelist, Gladiator, Halfling Outrider, Lasher (which has a minor supernatural whip attack at 10th-level though), Master of Chains (which likewise has a minor supernatural ability at 10th-level, animating some chains), Order of the Bow Initiate, Red Avenger (unless you count monk-like ki abilities as magic; the Red Avenger doesn't require monks or lawful alignment, and doesn't teleport or anything like a monk, but does focus on ki tricks), Warmaster, and Weapon Master (which also has a few minor ki abilities to boost weapon damage and such)).
From Song & Silence, though less warrior-oriented and more skill monkey-oriented, there's the Dread Pirate (one or two minor magical abilities), Outlaw of the Crimson Road, Royal Explorer, Spymaster (minor magical qualities), and Thief-Acrobat. From Masters of the Wild there's the Exotic Weapon Master and Tempest (other suitable PrCs in there are just too broken for any halfway attentive and halfway intelligent DM to allow; I've only seen them used in games where the DM was a newbie who just allowed anything, and games where an experienced DM had allowed almost anything just because he didn't have the time to actually look over anything for consideration).