The Chelsea is located in BFE, err the 4th floor in The Cosmopolitan. It was a trek to get there, but we made it! They have plenty of customer service there to help you. You get right in, with no problems. Everything is very well organized!
We saw The Black Keys, with Big Boi opening. We got there while Big Boi was on stage and made our way over to the bar. (I think there a few bars in the actual ballroom) For like 4 drinks, I think it came to something like $40. So, $10/drink... one corona, two vodka cranberries and a whiskey sour. Really? Whatevs.
There is general admission, which is on a carpet floor in front of the stage. Behind that, is what looks like bleachers set up with seats. So glad that we opted for General Admission instead of those seats. Note: the floor was moving like crazy when The Black Keys started. So if that freaks you out- get used to it!
One downside- it was hotter than HELL in this place! Everyone was drenched in sweat. I felt and looked like I just ran a marathon. Totally inappropriate. But Big Boi and The Black Keys fucking rocked it out HARD last night. The sound is GREAT in this place and they have two large TVs, one on each side of the stage, so you can see all of the details.