Improved Blindsight is not a WotC feat, according to http://www.wizards.com/default.asp?x=dnd/lists/feats
Blindsense is in Complete Adventurer, but I don't have that book
Blindsense is in Complete Adventurer, but I don't have that book

Dr. Awkward said:If it were me, I'd just grant blindsense 30'. The character will still need to buy Blind-fighting, but from the perspective of the DM, I'd say trading normal vision for half-assed vision is an acceptable transaction. It'll make the character playable, with that "I'm blind, but I can keep track of stuff because I'm so good at hearing" shtick. Keep in mind that even with blindsense, you still move at 1/2 speed. I'd allow the character to use Blind-fighting as a prerequisite to getting blindsight 5' radius, and then later expand that radius, achieving true Zaitoichi-like mastery of his environment.
Cabral said:The Psionic Power is Synesthete.
Taloras said:If you are allowing the Arms and Equipment guide, the Blindfold of True Darkness grants blindsight out to 60 feet at a cost of 9000 gp and covering the glasses item slot. Immune to gaze attacks, etc that require vision, but blindsight(not blindsense) out to 60 ft. You may not use any other form of vision during it (so if you are a beholder, you have to close all eyes to use it lol)
Mistwell said:I agree, that is probably the best answer to your question, if your DM allows it.
SRD said:Synesthete
Psychometabolism
Level: Psion/wilder 1, psychic warrior 1
Display: Material
Manifesting Time: 1 standard action
Range: Personal
Target: You
Duration: 10 min./level (D)
Power Points: 1
You receive one kind of sensory input when a different sense is stimulated. In particular, you can either feel light or feel sound. You can shift your stimulated sense between these two options once per round as a swift action Your senses continue to work normally as well, unless they are impaired for some reason.
Your face must be uncovered to use this power, because it is the skin of your face that acts as the sensory receiver.
If you are feeling light by absorbing ambient light onto your skin, you have your normal visual abilities (except for darkvision), even if your eyes are closed or you are blinded. If your eyes are working normally, you gain a +4 circumstance bonus on all Spot and Search checks. While feeling light, you are immune to gaze attacks.
If you are feeling sound by absorbing sound onto your skin and your ears are working normally, the expanded audio input provides you with a +4 circumstance bonus on Listen checks.
Psionic or magical displacement effects, invisibility effects, illusions, and other similar effects confuse your synesthete senses just as they would your normal senses.
You can also use this power to see sound if you are deafened, or hear light if you are blinded, thus removing all penalties associated with either condition (though you gain no bonuses for using the power in this way if you are not deafened or blinded).