Optimizinig event guide website

[simpleone]

I run an event guide where we list events from all local organizers.
The problem I have is that Google prefers old listings. For example if there is a listing for concert of Madonna for next month and we have an old listing for her last year's concert, then Google will prefer the old one and show it in its search results.

Another problem we face is that many listings get really bad position in search results - like on 10th page. Even though our website is very well visited and for many static keywords we are on the first position.

I assume that this is happening because structure of event guide is just the opposite to news site. When an event is first entered it could be a month before it will start and so it is put on page 30 (due to big number of events we have one page per day) and it will get to front page only on the day of the event. Unfortunatelly this is also the last day the event is relevant.
Whereas on a news site article is first published on front page and then it slowly drifts away into archive.

Any suggestions how we could tell Google to put more emphasis on new content versus old?