In my experience, and from other postings in this forum, these USB memory sticks don't need any driver installed for Win ME, 2000, NT, and XP; but they do need a driver (one came with my stick) for Win 98. I have used mine with ME, 2000, and XP and it's recognised automatically. I also use it with 98SE after installing the supplied driver.
When your PC says "driver required", you should be able to select an existing Windows driver, rather than let Windows search for one. I've had to do that with other hardware in the past. I can't remember the steps, but other forum users should be able to help you in that.
If there really isn't an ME driver on your PC, could it be that ME was installed in "minimum" or "custom" mode, without all the drivers? In that case, what you need might be on the ME CD.