You're trying to shoot a very difficult shot. You have a range from shadows->highlights that exceeds that of most digital sensors. In this case, you would've have to had picked which part of the scene you wanted properly exposed. If you wanted the highlights exposed, meter off of them and, well, lose some shadows =)
That is, if you wanted the words on the canopies readable, you would've needed to reduce your exposure so that you didn't blow out the light canopies. You can't really recover blown highlights. (You can't also 'create' shadow detail the sensor couldn't register.)
There's obviously a _lot_ more to this than what I've stated, but its your starting point - in such a scene, it's incredibly difficult to get a perfect exposure for everything. Work instead on exposing which part you want properly exposed.
Here're some helpful links:
http://www.cambridgeincolour.com/tut...hotography.htm http://www.joereifer.com/words/?p=272 http://www.anandtech.com/digitalcame...oc.aspx?i=2351
!c