I've been looking into this and it's straightforward-ish. The greaseweazle is a new fairly low cost disk controller, and you can couple that with a 5.25" enclo

I've been looking into this and it's straightforward-ish. The greaseweazle is a new fairly low cost disk controller, and you can couple that with a 5.25" enclosure for a CDROM/DVD. The cheapest way is to buy an old full size external CDROM/DVD drive, then scavenge the case.