Well, one
piece of open source software I'll certainly be using is
Audacity, for editing audio files. It's as good as anything
around for simple podcast editing. GIMP is *not bad* for photo
editing although I'm much more familiar with Photoshop (and
more qualified to use it).
I'd not consider GIMP "fit-for-purpose" for heavy/major
image work. I use it (because I work on Linux) and it is a
pain in the... compared to Photoshop.
When it comes to design for brochures and booklets (for
example) I'd use Adobe Fireworks to create any graphics or
images I'd need.
Have you tried Inkscape (FOSS vector image editor)? I used
to use Fireworks a lot and Inkscape turned out to be,
surprisingly, a worthy upgrade on that. But there can be a
learning curve if you're only a casual Fireworks user. Worth
considering.
Hopefully
the above answers Tom M's question too. Beyond those pieces of
software I can't imagine I'd use the rest of Adobe CS at the
moment - although Dreamweaver may be useful for designing
emails to members and donors.
Oh noes! Please don't :P
Maybe try something like MailChimp's campaign editor
(literally the best mail design tool ever!). Dreamweaver sucks
bad enough for creating websites, let alone email ;) In fact -
it might be worth looking at MailChimp for the Chapters mail
campaigns/correspondence.
On the main topic: I have a few CS Licenses kicking around
which may include some of the software you need (no promises,
I just know they exist somewhere, not the state of them :P).
Let me have a look.
Tom