The hunter becomes the hunted.

[TheCorsairMalac]

My adventuring party is being stalked by an archer assassin who calls himself 'the reaper'. He's an opportunist who strikes with poison from extreme range when we're in other battles. Naturally we're trying to track him down, but my character in particular (being an awakened animal, and a predator) absolutely hates being hunted. Fortunately we just looted a dragon's lair, so he's got gold to spend on the issue.

The game is D&D 3.5, all books are OK. What items do you know of that could help turn the tables on this hunter?

[sleepyphoenixx]

What's your level? How much effort it takes to find and kill him depends a lot on what resources he and you have available.

At lower levels a scroll of Scrying followed by Teleport is probably all you need. If he has Mind Blank up and sits in a location warded with Forbiddance things get a little more complicated.
You can also wait until he attacks and try to get him with Divine Retribution (CC), though you'll want to maximize and empower it to make sure he dies.

The alternative (tracking him down by mundane means) is pretty much doomed to fail unless he's seriously incompetent. Pass without Trace alone will ensure you'll never find him and it's pretty cheap to get.
You could try to get some fast flyers with good spot to find and mark him for you before he slips away. Summon Dire Hawk (RoTW) or a familiar or animal companion would work, as would a Druid or Ranger with Wild Shape - (Dire) Eagles, Hawks and similar animals with high spot should be capable of finding him, especially if you further buff their spot checks.

[daremetoidareyo]

I'm sure that there is a magic item that grants the deflect arrow feat

[sleepyphoenixx]

I'm sure that there is a magic item that grants the deflect arrow feat

Deflect Arrows doesn't help against attacks from ambush since you need to be aware of the attack to use the feat.
It also only stops one attack per round, which doesn't help much against a dedicated archer, and it doesn't do anything to stop the guy.

[BowStreetRunner]

Periapt of proof against poison (http://www.d20srd.org/srd/magicItems/wondrousItems.htm#periaptofProofagainstPoison), Skin of Fiendish Embrace (MIC p170), Snakeblood Tooth (MIC 136), Talisman of Undying Fortitude (MIC p188) or just some potions of Neutralize Poison.

[TheCorsairMalac]

@BowStreetRunner

All those anti-poison items are great ideas! I particularly like the snakeblood tooth. It has a sort of 'grunge' appeal that would fit our campaign nicely.

@daremetoidareyo

Deflect arrows would be nifty, and you're right, there are some items that grant it. A pair of bracers I think... As sleepyphoenixx said, it won't protect against the first shot(assuming he catches us unaware), but it would work wonders on later rounds.

@sleepyphoenixx

Your suggestions are good. We're only level 8, so scrying is a potent option, and we even have one of his shed disguises to increase the save DC. He doesn't have pass without trace, as I was able to track him by scent last time, but he escaped into a crowd. Unfortunately, the range penalties on spot checks(We're talking about ranges approaching 2000ft using dragonbone greatbow cheese) and his deadliness with a bow would make aerial scouts little more than temporary targets.

[Talar]

There is a ring in the Magic Item Compendium called Ring of Entropic Shielding or some such. Grants a continuous 20% miss chance against ranged attacks. Seems ideal against an archer enemy.

[Flickerdart]

Unfortunately, the range penalties on spot checks(We're talking about ranges approaching 2000ft using dragonbone greatbow cheese) and his deadliness with a bow would make aerial scouts little more than temporary targets.
At that range, there is no way to tell illusions from reality. Get some image spells all up ins.

[Garktz]

What about using ilusions to fake a fight and ambush him back?
If he.s shooting you from that far, it would be hard for him to tell the diference...
In case you want a most mundane fashion, make sure he follows you through a narrow space faking you are wounded, so he.ll try to hunt you down, hide and attack as soon as you spot him.
Sewers are a perfect spot for this kind of stuff.