Yo, I suck at HTML and CSS so bear with me this page will look very bad!!! also this is for just ripping and stuff and no MIDIs!!! for MIDIs go to here!
I strongly recommend GameGuy444's ripping tools. However they have gone unmaintained so I decided to do it myself. Download it from here and see the file "wii2wavV2.txt" for docs.
You can just put the ROM in VGMTrans and it should work fine. Just make sure to check accuracy, then right click on the music file you want to export under Detected Music Files (you should see Export To WAVE or something).
To download VGMTrans, scroll down to the table in README.md and click the link under Build Available (sorry FreeBSD!) then click the latest commit and scroll down to Artifacts then click on the build w/ your OS name (or be a cool kid and compile it from source). If it isn't there check the commits until you find it.
Note that these builds might be unstable and music might sound slightly off! Just be aware of this plz ty!!!!
Obtain a .GBS file of the game music you want to rip (or do it yourself but most games already have .GBS files ripped of them). You can get GBS files from Zophar's Domain or from joshw's website.
Once your have your .GBS, grab mmitch's GBSPlay utility. Windows users can build with Cygwin, installing gcc-core and make (or grab the pre-compiled binaries here). Linux users usually have both tools built in, if not use your package manager to install make and GCC.
To export as WAV, add the parameter -o wav to the command, like gbsplay -o wav foo.gbs. A player should pop up in the window, it will start exporting WAVs of subsongs. There should be a menu with keybinds popping up, use those as instructions.
Due to the primitiveness of .GBS files, no loop/playback detection exists. You will need to manually add fade-outs and endings.
Obtain a .SPC file, or rip these by yourself. You can get SPC files from Zophar's Domain, joshw's website, or snesmusic.org.
Once you have your .SPC, get DGRFactory's SPCPlay utility, and open the file from there. For the highest quality, set Bit to 32-bit (float) and interpolation to Sinc Function. To export as .WAV, click "SAVE" and select .wav from File Type in Explorer.
Obtain a .NSF file, or RIY (Rip It Yourself). You can get NSF files from Zophar's Domain or joshw's website.
Once you have your .NSF, download Brad Smith's NSFPlay utility and drag your NSF file onto there. I would suggest turning Quality in settings to the max on the slider. Export to WAV by clicking the rightmost button.
All songs from NSFPlay are by default 3:00 long. To avoid this set "Enable playtime detection" and "Save the playtime when detected" to a check in the settings.
For New Super Mario Bros. Wii, the filesystem for the soundfiles can be found here.