You need to investigate how to build a midi controller, and you need to publish it on a webpage ?
I assume that the "linked IP address" is the URL of a webpage.
To publish your findings, you could use: http://www.wikispaces.com/
It takes a few days to learn how it can be used, but you can have a nice webpage very easily.
Now your first question: Is the Arduino any good for midi?
The answer: Yes
Is there an other platform or microcontroller better suited for building your first midi controller?
The answer: I think there isn't. Arduino is best for quick and easy building a first prototype.
There are many examples and libraries for midi. You can ask questions in this forum at the "Audio" section.
Start to read here: http://arduino.cc/en/Tutorial/Midi