Hey there! i'm making a hack and need some midis of some classic sonic music (You Can Do Anything for example), is there a site hosting all of that? and is there any mandatory crediting needed? please let me know!
One of the most complete resources is http://vgmusic.com/. And yes, they do have "you can do anything". Keep in mind that the MIDIs on that website are fan-made for the most part, so their quality can vary greatly. I can't tell you if their "you can do anything" is any good right now because I'm posting from my phone, but I see it's been sequenced by King Meteor, who is usually extremely good.
I managed to find one of the themes (the speed up theme from 510, which is you can do anything) and it sounds GOOD in sonic 1!
I'm going to correct you on one little thing: they're MIDI *files*, not MIDIs. You're not searching for music instrument digital interfaces. You aren't the first, nor will you be the last, to say that. But I like to at least make people aware of what they're really saying.
Hey there! i've noticed a huge problem with alot of these midis : Converting them, then putting them in the game has a weird effect, why does the music take so long to flippin' start?
You're gonna have to edit the MIDI files to work properly in game. Not only just to remove things like that, but also to properly map the channels to the YM2612 and PSG channels (which would include having to do some rearranging if there's a lot going on, especially with chords involved; those will have to be split out into individual channels). Try giving this a read for starters.