I'm looking for some great advice -- and perhaps some unusual tips --
on how do you get just the right amount of sweetness in chocolate. 
For buying chocolate to eat, for baking with chocolate and for making
chocolate candy.

Whew. This is a real judgment call. The perception of what is the
"right" amount of sweetness can vary widely.

I like sweet milk chocolate very much; my husband prefers dark
chocolate of the type that used to be called semi-sweet; my mother
enjoys chocolate that is so bitter that it sets my teeth on edge. All
of us find that our choice of chocolate has the right amount of
sweetness.

Hi curiously-ga!

You might enjoy this site (Yummmmmmmmmmmmmmm!):
http://www.chocolatesource.com/glossary/index.asp

Sincerely,
Boquinha-ga

You can look through this book and experiment:
http://www.kk.org/cooltools/archives/000203.php
It's a nifty guide to new horizons in chocolate appreciation.  There's
an experiment on p. 124 that involves making a chocolate mousse and
trying it with a pinch of different condiments on top, such as
lavender blossoms, ginger, ground pink peppercorns, and palm sugar. 
This isn't as off topic as it sounds, because the ingredients you add
to your chocolate have a strong effect on the amount of sweetness your
taste buds perceive.
And if you want to focus on the sweetness of pure chocolate, the book
has some great suggestions regarding cacao percentages, brands, and
sources.

Finally, let me mention the best candy bar I have ever eaten:
http://www.vosgeschocolate.com/Merchant2/merchant.mv?Screen=PROD&Product_Code=ECBNAGA&Category_Code=NGC
Curry and coconut interact with 40% milk chocolate to produce JUST the
right amount of sweetness, as far as my taste buds are concerned. 
Your opinion may differ, and discovering why or why not is at least
half the fun.

Bon appetit,
Carl

P.S. This is completely off topic, but pistachios are great in chocolate bars:
http://www.tulumba.com/icy_itemdesc.asp?ic=FB424349YV686

I recently had the honour of taking in a presentation from the
president/CEO of a major N. American chocolatier. Among her various
job responsibilities was to regularly taste random samples of the
various chocolates made in her chocolate factory, to ensure that they
"taste right". Even though the extremely precise measuring equipment
used these days in her factories just about guarantee that the exact
same amounts of ingredients go into every batch, little variations in
the quality of the raw ingredients (sugar, milk solids, filling
ingredients, etc.) along with environmental factors all play a part in
the final flavour of the chocolate.

Yes, I along with everyone else at the presentation expressed our envy
at that part of her job, and marvelled at how she was able to stay so
fit in spite of it!