[Summerleft]

Hi Fi,
Well for selling prints, you can get a free website at freewebs.com which enables a checkout and uploading of images, or I am with Photium for £7.27 a month you can upload pics and add checkout, Photium has the advantage of being reallllly easy.

I suggest getting cards or leaflets with the web address and your details on so you can leave them lying around for people to pick up at the event.

You will need more than one memory card but might manage with one battery if you take your charger.
Each time you fill up your mem card wrap it in paper and note on when or who you took the pics of, I also write down peoples names, its funny how you remember people. Its not full proof but its ok, anyway most people are happy to looks through portfolios which say for example award ceremony room 1 on them.

Im no expert of the settings and lighting but from expereince I personally would worry about not having an external flash for an event like that, obviously as you know noise is a problem when doing things in poor lighting too but will leave the rest to the more experienced on the forum, all I can say is I struggled with my event in poor light on sunday without an external flash or V fast Lense.