Until Pro Tools 9, the software was tied to Avid(digidesign) hardware. You either had to get a Digi 003($3000 at release) console or a C24(at the low end of the scale which is around $9000). You can find a used Command 8($500 or so) or just find a reasonable control surface. Be warned though that most products will not have the greatest support. You could try the Steinberg CMC controllers which start at around $130. I don't know what the support is like for Pro Tools though.

You should note as well that even if you had Pro Tools 9, a mixer would do you no good once everything is in the box. Mixers mix. They don't control DAWs. A contol surface controls a DAW.

There isn't anything that you can't do in ProTools with a mouse. Everything can be automated with just a mouse. I actually have a friend who has a Avid/Digi C-24 that she spent nearly $10,000 US on and all he uses is his mouse and not the control surface much. ProTools already has a GUI of the mixer in the software. And you use it just like any other hardware mixer controlling it from your mouse. You insert your automation markers and drag your levels and pan pots around along with your EQ, effects sends, etc.. It's a no-brainer and no problem. The control surfaces like the C-24 can be a handy commodity but it's not a necessity by any stretch of the imagination. A lot of folks have become very adept and proficient with just mixing with a mouse. Of course this would not be something you would attempt to do in live situations. And that's where you would need to control surface even more. Not only will it automate the software, it allows for real time mixing.

There's no end in sight
Mx. Remy Ann David

i didnt know there was a difference between a control surface and a mixer--what i want then is a control surface--is there a similar compatibility problem with most control surfaces?

Really, a control surface is generally designed to work in an integrated way with certain software packages. It's not necessarily compatible with all software packages. Many control surfaces also double as digital mixers when they are plugged into a computer and the audio input/output interfaces. A digital mixer simply indicates most of that computer functionality is built into the mixer which can be used as a standalone device that even records and plays back. Control surfaces can be as little as $1500 to over $80,000. Don't think you're going to get all of the capabilities with the $1500 unit that you will $80,000 unit. And in all likelihood, you'll be utilizing ProTools? Are you an expert ProTools user already? No? Then you may need to lay out thousands of dollars for proper training to utilize that control surface with the software properly and effectively? This crap ain't necessarily easy to comprehend much less utilize. So you really don't know really, what you need. You only know what you think you want. That's not necessarily what you need. It's a dream that perhaps is not quite ready for prime time. I didn't just exactly jump into building my Remote Truck, CROWmobile.com without having first spent 20 years designing and building other control rooms, studios, broadcast facilities and using everything. Then, 20 years ago, I was finally ready to build my Remote Truck from the over $150,000 I had saved up from working at NBC-TV for 20 years. Now what do you think you need? Think about this carefully as the clock is ticking.

Time's up! Your answer please?
Mx. Remy Ann David

Remi brings up some great points. I don't use a control surface at all. But, I am a gear hungry butcher. If you are set on a control surface, you might consider a presonus fader port.

Okay here is a little more digital trivia. We have to use the way back machine now. When the Cold War came to an end, military grade DSP processor chips were no longer a single proprietary item for the military anymore. So a consortium of folks went to work on one of the world's first digital consoles. It was nothing more than a rackmount blackbox. It had analog inputs and outputs. I believe AT&T, SSL, Bell Laboratories & George Massenburg came up with this device they coined DISQ. It had to be coupled with an SSL 4000 with " Total Recall ". The SSL 4000 became nothing more than a control surface where it's automation information was sent to the blackbox and everything was plugged into and came out of the blackbox. Not sure how many of those were actually ever sold? A few were.

I got to meet Mr. and Mrs. Gorbachev around that time.
Mx. Remy Ann David