Creatures of the Incorporeal subtype are a pain in the ass for most characters. Unless you're kitted out in the right way, you're going to suffer that 50% miss chance.
Fortunately, Psionics has quite a few different options available. But which options are best? This thread will explore that question.
Powers:
Concussion Blast
The first available option, and very straightforward: you manifest it, it does Force damage. Many call it the Magic Missile of Psionics.
Pros: Available as soon as level 3. Damage is guaranteed, except for creatures with Power Resistance.
Cons: Crappy augments. Low damage-to-PP ratio. It's blasting, so it's inefficient.
Astral Construct
High level ACs get access to Concussion Blast as a Menu C option.
Pros: Free blasting; you manifest it once, and it keeps on going.
Cons: Only available with 7th, 8th, or 9th level ACs, so most Psions won't be able to make use of it until 13th level. Shaper-specific power.
Telekinetic Maneuver
It's a Force effect, so it works.
Pros: Lasts for multiple rounds, so it's PP-efficient. Incorporeal creatures often come with nasty touch attacks, and this can keep them away.
Cons: The only guaranteed-to-work maneuver is Bull Rush, so you can't do actual DAMAGE with the power. To be effective, requires a teammate to coordinate with you (you Bull Rush, they swing at the thing with an AOO) or a damaging effect you can push the target into or through, such as an Energy Wall.
Telekinetic Sphere
An effective trap for any Incorporeal creature.
Pros: Stops 'em cold. Gives you the option of leaving instead of fighting.
Cons: Eventually it will get out. Doesn't do any actual damage.
Psychic Scimitar
The sword this power creates is Incorporeal, so it can affect Incorporeal creatures.
Pros: Lasts a long time. If you get multiple attacks, you can make multiple attacks with it.
Cons: If it gets destroyed before the power is up, your key ability score takes damage.
Amethyst Burst
Only available to those using Dragon Magic material. Does AoE Force damage.
Pros: Better damage-to-PP ratio than Concussion Blast. The fact that it's AoE makes it more PP-efficient.
Cons: Allows a save. Augments aren't very good. Close ranged AoE, making it hard to avoid hitting allies.
Gemstone Breath
Also Dragon Magic-only. One of the augments is a Force effect.
Pros: PP-efficient, as it works over multiple rounds. Adds up to good damage.
Cons: Allows saves. The Force effect augment isn't available until mid-to-high levels.
Dream Spirit
Found in Secrets of Sarlona. Creates an Incorporeal "creature."
Pros: Lasts for multiple rounds. Acts independently.
Cons: The book fails to include a full stat panel for the creature so, by RAW, the thing can't move. The damage is rather mediocre.
Feats:
Transdimensional Power
Lets powers that otherwise would be subject to Incorporeal creatures' 50% miss chance bypass that miss chance.
Pros: Can be tacked on to any direct damage power. By RAW, can be tacked on to any power, period.
Cons: Requires a feat, of which you get far fewer than you do powers. If you're not up against Incorporeal creatures, the feat is kinda useless.
Analysis:
The ability of high level Astral Constructs to dish out an augmented Concussion Blast once per round as a free action is the best way of dealing with Incorporeal creatures. Unfortunately, it takes a lot to get to the point where that is an available option. For some Psions, it never will be.
Gemstone Breath is a close second, but once again it is only a higher-level option.
So what's a nascent Psion to do? Here's where it gets fuzzy. Each option comes with its drawbacks. For example, Concussion Blast does lousy damage and takes up a power slot at a level where there are lots of other, highly-attractive powers available, while Transdimensional Power requires a precious feat.
This is, in fact, a gray area where I've been unable to make any solid conclusions. Right now I'm leaning toward Telekinetic Maneuver combined with an AoO-ing companion or an Energy Wall as the preferable method, but this is far from ideal.
Thus I turn this over to the Min/Max boards for input.