If the Moon or Mars will we . . .

mmm... good one...

> If we're going back to the moon I wonder if they'll launch like
> Apollo or will they try for some orbital assembly?
>
> If Mars is the next mission then I think orbital assembly will be
> required.
>
> Because of the high inclination of ISS I think we can discount using
> it as a base platform.

for such a major project it could probably be relocated... certainly cheaper
than building a new assembly bay from scratch...

> So, what are the basic pieces of equipment needed for on-orbit
> assembly?

The simple answer is that depend what you want to assembly... ;)
The ISS or something similar would provide all it's needed for major
on-orbit assembly, short of a custom-made pressurizable assembly hangar of
some sort, which I doubt it would be needed really but could eventually be
added easily.
Given the costs involved I imagine as much as possible of the existing
equipment would be re-used, although this is obviously not always the case,
for instance shuttle fuel tanks are (sorry, were) still routinely dumped,
while they could be very cheaply brought up to orbit and recycled, if
nothing else as spare tanks...

> Will the pieces of the ships be launched into orbit and assembled
> there or will some sort of rudimentary assembly bay be constructed?
> If the latter will there be any life support included or will the
> astronauts base themselves in a shuttle-like vehicle and ferry over
> for the assembly work?

I think the only practical assembly facility, if you discount the ISS, is
the shuttle bay itself... unless you're talking very very far in the future,
there is a major issue with introducing new stuff, like ferry vehicles etc.
they need to be designed, developed and tested, which makes them incredibly
more expensive than what they will be anyway just to make. This sort of
inertia is behind many strategic choices, like for instance the shuttle
update program, is not that the shuttle is particularly good, in fact is not
nearly as good as originally hoped for, but it does exist already, and even
if partial redesigning and major upgrades are required is still immensely
cheaper than design a new vehicle from scratch... not saying a new vehicle
is not in the coming, at some point, but as far as where the money available
right now is spent, those are the main issues I think...

A bigger question to me would be how are we going to send all that stuff up?
Even once the shuttle return to normal operations it isn't an optimal
lifting mean by far...Russian rockets would be more efficient but they are
not large enough to carry what is reasonable to assume will be loads of big
heavy payloads... my guess would be that the theoretical best approach could
be to take a Titan, or even a Saturn, which are good solid and proven
designs, and convert the engines to burn a better fuel, like oxygen-rich
mixes of kerosene, RD-180 style.
Sure, design a brand new lifting vehicle on purpose would be much better,
but would be immensely more expensive and tackle much longer to be ready...
pretty much the same basic concept would apply to on-orbit assembly, if you
have unlimited budget and ten years to spend on designing a special orbital
facility cool, but if you have an administration that decide to risk public
blame investing in such high risk operations, and will only give you a very
tight budget and will wants results yesterday, which is a more likely
scenario unfortunately, then relocating the ISS seems harder to beat as an
option...

cheers,

Claudio