For those of you lucky enough to already have the Transmit FTP Client, it works quite well with iGOG file transfers. A nice extra is that you can use it to easily delete multiple unwanted MID files at the same time on your iPhone/iPod Touch, or to change filenames.

I had downloaded FileZilla, as suggested in the Help file, but it wouldn't display the MID files, despite repeated tries.

Hope this tip helps someone!