For those monks who do not have a generous patron feeding them magic items, you might need to obtain equipment by (shock) running quests yourself. Following is a guide to some key named items from existing quests that are good for monks.
Waterworks
Black Widow Bracers- *** the +4 Armor bonus is so important, although you can replace it with Mage Armor potions equally well.
Sewer Smock- switch it in for acid arrow spells or occasional harbor traps
Graskitch's Skullcap- +1 wisdom can turn into +1 AC when combined with Monk Wisdom I. However, low-level monks will generally have their head slot taken up by a Hat of Steady-Spellcasting.
Catacombs (now 100% slime-free!!)
Mask of the Asylum- *** +5 concentration makes it important to get this at low level, or something similar.
Cloak of the Asylum- an unusual slot to get +1 wisdom
Robe of Duality- not only does this robe give you +10 hp, but it has the best graphic design ever
Pillar of Light- a +1 quarterstaff of pure good will help you kill Ghostly Skeletons in Delera's Tomb
Shan To Kor
Shadow Star- *** hurray, someone to get use from the +1 Keen Returning Shuriken
Trapblast Goggles- obviously, you want high reflex to get the most out of the Evasion ability
Gatewarden's Girdle- you may as well start building up fortification
Cloven Jaw War Beads- +2 constitution isn't bad
Splinterskull
Spider Silk Robe- DR 3 against slashing, not bad
Visor of the Flesh Render Guards- cast Deathward on yourself, which is important because it'll be a long time before you get a cleric in your party (or any other non-monk)
Splinterskull Acolyte Ring- the Improved Devotion will boost Healing Ki I.
Zulkash's Bone Necklace- +2 wisdom, not bad
Splinterskull offers several other items giving good stat bonuses. However, completing 50% of Splinterskull on Hard will unlock House Philarian favor, enabling you to buy +4 stat buffs for 30 minutes at a time. Those buffs are generally superior to wearing stat items, until you eventually get +5 and +6 items.
Delera's Tomb
Voice of the Master- you want XP, right? This thing is +5% XP.
Cult of the Six
Snowstar- +2 icy burst returning shuriken, it's the best ranged weapon a monk will get for a long time.
Shrunken Head- yes, monks have good saves already, but +3 resistance helps when you need it
Quicksilver Cassock- attractive to monks, but seems to not stack with the Fast Movement class feature
Threnal
Spectacular Optics- replace your trapblast
Theurgic Stave- +1 adamantine quarterstaff is possibly more damage against golems than an adamantine kama, if you have Power Attack
Vault of Night
Ironweave Robe- +5 armor bonus, at last an upgrade to Black Widow Bracers. However, you may want to just get White Scale Robe instead
Helm of Mronanon- +6 wisdom is nice for monks, but you'd probably want to get it on a Green Steel item of Existential Stalemate instead.
Twilight Forge
Visor of Concentration- +10 concentration to your Ki in the goggle slot, how nice! However, you can now build Tempered Green Steel Goggles with +10 concentration plus other bonuses.
Nullcloth Gown- a trap. Monks might suffer spell failure on Healing Ki while wearing this. And they already get Spell Resistance as a class feature. And resist 10 to some other energies isn't worth much.
Chattering Ring- everyone likes +3 AC. Too bad your chance of ever getting it is tiny.
Shining Cresents- sadly, although it uses the quarterstaff animation it's technically a sickle, so monks can't use it with their powers. Hopefully the devs have updated this item to be a "Ki" weapon now, but that's doubtful.
Gianthold Tor
White Dragon Scale Robe- This'll be the official uniform for high-level monks. It's no surprise that the DDO producer wears it on her monk.
Reaver's Fate
Dreamspitter- Hey, +5 staff of greater evil outsider bane. Such a shame it doesn't penetrate any DR. However, for a high strength monk facing a high-AC devil, the huge +9 attack bonus could make it your best choice.
Black Abbot
Litany of the Dead- monks need high scores in many abilities, so +1 to every score can really help
Shroud of the Abbot- a trap. And an unsubtle trap, because the fact that it inflicts extra damage when you're hit isn't hidden. Deathward could block it, but still the item offers nothing good enough to make that sacrifice.
Staff of the Petitioner- sadly, there's nothing on this quarterstaff to make it even slightly attractive to a non-spellcaster. It has +5 concentration, which isn't enough to benefit a monk of such high level.