Digital camera novice needs help

Hi - I've just purchased my very first digital camera - a canon
powershot a85. I know relatively little about photography - digital
or otherwise and hoping someone would be kind enough answer a few
questions and help me get started.

I've purchased the camera primarily to take pictures of the sky. I
was inspired by witnessing a truly amazing sunrise at glastonbury
festival this year realising in a small but healthy obsession with
the sky, clouds and sun. I would also like to be able to take some
close-up shots.

So I've bought the camera, batteries and recharger, a 512mb cf card
and a case. What else do I need to get started? Are there any
lenses or filters that would be particularly suited to the sorts of
pictures I want to take? And do i need an lens adapter to fit these
lenses to the camera. Oh, finally, can I use any lenses/filters on
the camera or do they have to be ones especially made for digital
cameras? I am trying to set myself up as economically as possible so any advice about where to buy stuff would be eally appreciated.

Thanks very much in advance. I hope to have some photos to share
with you very soon :)

Sarah