Esite un'utility che permetta di rippare la musica e i suoni usati nei giochi DS ?

Oppure esiste una serie di procedure che permetta di farlo?

I thought I'd mention that the Nitro Composer music format has already been hacked on the DS. It's a bit complicated to get to it, but it can be done. Not all games use it, but most do (mostly Nintendo games, but some others do - the only non-Nintendo game I've tried is Cooking Mama, but I've heard quite some others also do).
Here's how to get it:
There are 2 ways.
The first is more complicated, but allows you to get streamed music.
You need to extract the ROM's filesystem using NDSTool, NDSTS or NDSHeader. Then you will get a bunch of files. You need to find one called "sound_data.sdat". Some are named differently (Yoshi's Island DS uses "YOSHI_DS.sdat" for one of the 2 sound data files it has) but they all have SDAT extensions. If you can't find these, the game doesn't use the Nitro Composer format.
Next, you need to get these. The method I'm familiar with is a program called "sdattool". It's a command line program.
First, you need to use it (I'll provide it later). Run it with this parameter string: "sdattool -x sound_data.sdat" (obviously, replacing sound_data if the name of the file is different).
It might be a good idea to rename the file to something that you can tell what game this is (eg. nsmb.sdat, yoshi.sdat) before you do this.
Next, a folder with the same name as the file will be created. Go in and you'll see several folders: Bank (instruments for sequenced music), Seq (sequenced music), SeqArc (not exactly sure what this is, but I believe it associates the sequences with the instruments and samples needed), Strm (not used much, streamed music), and WaveArc (sample archives - I don't know how to extract them, I have a program that converts the individual samples called "swav2wav" but it doesn't extract them. But you can still get the samples - I'll cover this later). I'll go through them in order.
Basically, the only ones you can access by this method are sequences and streamed music (some games mix up some a little - WarioWare Touched uses sequences for Wario's voices, and Mario Hoops 3-on-3 uses streams for the character voices and a few pieces of music).
First, sequences. You need "sseq2mid". It converts the sequences to MIDI files. Unfortunately, they usually sound awful, as the instruments are all messed up.
Next, streamed music. You need "strm2wav". Just drag an STRM file onto the program (do this with SSEQs and sseq2mid too) and you will get a WAV file.
Really, there's not much you can get this way.
Now I'll cover method 2.
This is with a program called "VGMTrans". Something has gone wrong with the website for it, so I'll provide it later as well. It extracts everything except the streamed music.
First, open VGMTrans and drag an NDS rom into the window (not on the EXE, on the window, this is important). Then, if it doesn't crash, you will get lists. In "File List", the ROMs you have open will be displayed. In Detected VGM Files, you will see a list of the sample archives, sequences and instrument banks. In Item View, it will mess up the display. But if you select a file from the "Detected VGM Files" list, a list of samples/tracks/instruments will show up. If you select a sample archive, right click on the Sample ## in Item View to save a sample as a WAV. But this isn't too useful as there's something better.
Next, you can double-click on a file in Detected VGM Files to see a hex view of it. You can also select an item from Item View to see what portion of the hex view corresponds to that item.
Next, you can right-click on files in Detected VGM Files to save the entire sample archive as WAV (if you right clicked on a sample archive), an instrument bank as a DLS and a sequence as a MID (easier way to use sseq2mid, basically - both do the same).
Next, at the bottom you will see two panes: Coll Info and Collections. In Collections, you will see a list of all the sequenced music in the game. Click on one (beware, this can sometimes crash VGMTrans) and press Space, or select the Play button on the toolbar to hear the music, with instruments and all - but the readme states the DS's basic tone and noise channels aren't supported, so some tunes don't sound perfect. When you've got something selected in Collections, in the Coll Info pane you will see the banks, sample archives and sequences that make up one "collection", as the program calls it.
I think this is all now.

A few other things also:
Sseq2mid can be run with parameters (run it in a command prompt for more info) to add stuff like loops to the MIDIs, which is where it's better than the VGMTrans conversion.
Something else I forgot to mention was Sseqseek. It's not too useful, but it analyses an SSEQ file and displays a rundown of all the data inside. I've also included it.

Here, you can download all this stuff: http://www.sendspace.com/file/qln9a1
Note, also, that I made nothing of it other than this guide to it.