One of the major issues to confront is whether to put the date/explicit details in the ad copy.
If you put them in the ad copy, the CTR is usually lower (hence, can be more expensive to maintain the same position).
If you don't put them in the ad copy, then the CTR is higher, but the conversion percentage is generally lower.
For more information, purchase, etc type of campaigns, one of the best tactics that's worked is to also do free drawings for event swag (concert t-shirts, CDs, eBooks, etc - depends on the event) and maybe toss in a few free tickets in a separate drawing as well.
This gives you the ability to have users register without having to make a split second decision to buy.
With time based events this is very important for a couple reasons.
1. We value our time. Committing to an exact time period is something often people are hesitant todo.
2. Permission might need to be granted by a 3rd party (the gf/spouse for a concert, the boss for a conference, etc).
Therefore, it can be useful to offer a second conversion option besides just an ecommerce transaction. A registration allows you to contact people at a later date to stay in front of them and to keep their interest high.
As far as the above posts are concerned, it is best to set up an entire campaign first while keeping it paused. Let your rep know what you're doing and to please let you know when the ads are approved and ready to roll on search partners (and possibly content syndication) so that the campaign launches in a single complete stage instead of having it the traffic change as ads are approved for Google's traffic partners.