I have a 1911 type pistol, shoots great, is accurate and works fine.
The only problem is it kicks the brass straight back into my face each shot.
Do I need to replace the ejector,or can it be "tweeked"?

It could be a technique issue.  Stop shooting gansta style from the hip.  
Really I haven't a clue how to solve your problem...  Unless you're shooting gangsta style.

An extetended ejector would fix you right up.

Usually it isn't the ejector, it's the extractor.

It can be "tuned" to prevent this, but the techniques depend on what the problem is, and how it needs to be adjusted.  Too much to post here, and impossible without seeing the gun.

I'd suggest either a qualified pistolsmith, OR spend a few bucks on Jerry Kuhnhausen's book, "The Colt Automatic: A Shop Manual".

This has full details on how to adjust the extractor and if needed, the ejector.
This isn't difficult, but you need to do the RIGHT adjustments or you risk an unreliable gun, or broken parts.

Quoted: It could be a technique issue.  Stop shooting gansta style from the hip.

Yo!
Wass up wit dat!
Then I'd have to roll the window down all the way.

Thanks guys, I'll try the extended ejector first, before I go to a gunsmith.
I am quite capable of breaking my own weapons.

Gunslinger808,

My wife's 1911 was doing the same thing. We adjusted the extractor tension and now it works perfectly.

Check out this Extractor Adjusting Tool.

Coyote3,
That adjusting tool is neat, but why bother?  It's really easy to adjust the extractor with the slide and a bit of elbow grease.  

Maybe I'm just cheap.
Scott