This website includes a bunch of stuff, lots of chipmusic plugins. So far as I know, most of them shouldn't be requiring any special downloaders. I don't know whom you're speaking of, but as far as chiptuning goes, I've used Matt Montag's NES_VST (which you can download from the website) and, unless you want to use the NES's sample channel for anything other than percussion, it should be good for that need. VOPM is cool for Genesis stuff and even lets you import Genesis music files, so if there's a patch you enjoy from a particular Genesis score, you might be able to grab it and use it. And C700 enables much the same thing for the SNES, though it's a little older and sometimes glitches.