Archers' Standard (price: 4000 gp, source: Forge of War (Eberron))
Any allied archer who shoots an arrow or a bolt while under the effect of this standard [it affects your whole party] can ignore the first range increment. Thus, the attack does not start taking penalties until three range increments, rather than two, and it can travel as far as eleven range increments, rather than the normal maximum of ten.
It's unclear whether you're effectively 1 range increment closer for all purposes related to ranged attacks, or if it's only for purposes that are normally phrased in terms of range increments. But the generous interpretation does what you ask.
(You probably want to mount the standard on a backpack frame (price: 5gp, source: MIC), which lets you wear it as a shoulder-slot item. The other option is to mount it on a pole-arm, which is not ideal for an archer who's planning to stay away from melee and thus too far from your glaive-wielding friend to benefit from the AOE.)
Sharn race (source: Anauroch the Empire of Shade, or Monsters of Faerun)
Sharns have a whole bunch of unique abilities, one of which is that you can create small mobile one-way portals for you to attack through. The far ends of portals can roam up to 100 feet from you, thus effectively granting +100 feet range to all of your abilities.
caveat: 4RHD+5LA. Which can be worth it, but only if you're exploiting all of the racial abilities, not just the portals.