sfz files do not require a special tool to created or edit. They can be maintained using a text editor. There are hundreds of examples installed with the synths bundled with SONAR. Dimension Pro, Rapture, Session Drummer and several others play sfz files.
 
To see what an sfz looks like, assuming a default installation, the sfz files for Session Drummer are installed in "C:\Program Files\Cakewalk\Vstplugins\Session Drummer 3\Contents\Kits." When I was building kits by hand, I would copy one of the files in there and replace the sample references with my own.

And if you want to know more about how to create your own SFZ files...that's a link to an article I wrote for Harmony Central.

I think I have some definitive answers for you.
 
The Matrix isn't really optimum, because you can't trigger a one-shot properly. It's designed more for looping, so you have to hold the trigger key down for as long as you want the sound to last if it's not a loop. Nor can you really record the "hits" properly as MIDI triggers. 
 
Session Drummer does the job very well, but it has only 12 channels audio instead of the MPC-style 16 channels, and the drum layout is disorienting if you're not doing something drum-related. However, each channel can have more than one sound (for example, the kick can have two separate samples triggered by different notes). So if you don't need separate outputs or processing for every sample, this will take care of you. If you do, insert more than one Session Drummer.
 
Another option is Cyclone DXi, which is ancient but is the closest to "MPC-style thinking." It lets you drag samples on to pads, trigger them as one-shots or loops, and more. There are two big drawbacks that may or may not matter: The pads don't respond to velocity, and they don't have a MIDI learn function (although you can change them manually to respond to particular notes and channels). If you just want to trigger samples and don't care about velocity response, this is the fastest option.

Thanks!
 
I actually found the exact solution I was looking for, by installing two freeware applications. One is called SFZ Designer and is fairly easy to learn to create sfz files without text editing. Pretty nice. The other is called Sforzando, and is a VST and a stnadlone thing that loads sfz files and lets you play them. Lots of control and freedom, and easy to usde, and free! I don't knows what other people's needs entails, but for this little project, this fits the bill perfectly! Thanks for everyone's help.

Sforzando's "hidden perk" is that you can tap directly into Dimension Pro programs to see which keys are actually mapped to sounds. There are a few DP programs with only a few keys active, which makes it seem like DP is "not working" at times.

jkoseattle
One is called SFZ Designer and is fairly easy to learn to create sfz files without text editing.

Thanks for this link.  Nice to see that sfz is still alive in some parts of the world.