I'm sorry to hear that. I myself have purchased 11 (yes, eleven) 500 GB My Book drives and only had trouble with one. Here's two stories with them:
1. I ordered three drives. I was going to live with one 500 GB drive--I was upgrading from a compilation of 120, 80, and 40 GB drives! It was a huge upgrade! Then I started ripping to FLAC and noticed it filling up. My goal originally was to have my data on three distinct drives. Main drive with onsite and offsite backup. Unfortunately, I started needing 2 and 3 drives. I slowly added to my pile of My Book's. I paid ranging from $255 for the first few to as low as $180--this purchasing span went from about July of last year to January of this year. The problem I had was that I had all my data on all three drives and suddenly, one just quit working! I couldn't turn it on or anything! Luckily I had two identical copies but I'm positive I lost something--probably minor or just some folder cleanup that I have since accomplished. But I ended up sending that drive in. They didn't offer a SINGLE piece of advice or assistance for bringing the drive back online.
I'm thinking the USB part probably messed up and the SATA drive was probably fine but I didn't want to destroy the warranty and lose $200.
2. The second time was when I was copying data from my 500 GB My Book to my fresh software raid a while back. My chair, while I was spinning, caught the cable hanging off the desk and very quickly forced the RUNNING drive onto its side--fast! The drive actually shut off! I'm thinking it sensed a jerk and then quickly slid the head to its safe location for the impact. Luckily I still got my data back.
I guess your one of the few people that has the disappointing thread posting asking for help with a failed drive. I always worried about a failed drive and couldn't even imagine how horrible that could be...it never really happened to me yet, though. The two times I've had hard drive issues involved either simply backup data or system drives which didn't matter 'cause all my data is on the server.
Was it running when it fell? If yes, I wonder if it shut off like mine did? My drives were also the Essential edition (the cheap ones). I guess the Premium edition isn't shock resistant. If it fell two feet while running and didn't sense the drop--to save the head--then yes, that would be horrible.
I consider my music collection about as important as my other pictures and documents because, like you, I've spent a lot of time organizing it. Still, if you have the MC database, save that! You can possibly read through that to recreate your ratings and playlists. I'd take the entire JR folder--including backups and the current library and burn it to CD now. Burn everything you have to CD--database wise.
Since I hand scanned my cover art in and that isn't huge, I burnt it all to a DVD. Re-ripping the CDs would suck. Re-scanning the cover art would suck even more. Some of it required cleanup and some help to look good so I wouldn't want to redo all that.
I would also suggest taking it out of the enclosure and hooking it up directly via SATA and power. I've opened my My Book's all at least once--some twice. It is a pain but isn't horrible. I always end up breaking some clips but don't really care. Be a little careful since you're concerned with the drive!
Of my 11 My Book's and 6 external SATA 500 GB WD drives, I haven't had a single failure--remember that story #1 was probably just a USB board failure and not the drive. It wouldn't even spin up the drive when the issue developed.
Keep us posted on your progress (if any) and I'll keep thinking about it.