Yep, been there.
A few days before the actual event I got a phone call from Warner Brothers. The woman on the phone asked me what I was going to do in the weekend zeppelin played. After I replied that I was possibly going to change diapers on my kid, she told me that I had won the Myspace Led Zeppelin contest and that I was going to the show and the rehearsal on cost of Warner Brothers.
On the 9th we arrived in the Arena, and had to wait for quite a while, at least 300 other people were also waiting to attend the rehearsal. At one point we heard music, Zeppelin were starting to rehearse. After receiving a badge and beeing scanned mercilessly for tape recorders we were finally allowed to get inside.
The band was playing IMTOD and testing the different vocal effects.
It sounded quite epic, especially Jason's bass drum was deafening. After some plantations about "Second sight" we got a rendition of No Quarter, mostly without vocals.....Robert had walked into the arena to listen to his band play, while drinking coffee.
We also got a rendition of NFBM, some more goofy Plant dialogue about what would happen to the young ladies during the drum solo, and finally indeed a mini drum solo by Jason's son (Well done kid :D ..)
I also remember them rehearsing parts of the obscure blues called Honey Bee (some might know this song from bootlegs, it was once part of the WLL medley)
Once the band finished playing the big logo behind them appeared and some people from a charity action were invited to pose in front of it together with the band.
All in all a day to remember, still got the badge, as soon as I can scan it I will post a picture.
I also still wonder if somebody succeeded to record the rehearsal, would be a grande kick to hear it again.