You don't need Splenda at all for whipped cream.

Now if you want *sweetened* whipped cream, add as much as you want, and,
assuming you're using the powdered stuff, remember to count the carbs.

all you need to do to make whipped cream, is to whip the cream.

You just put in the beaters (or, if you like and want to use the arm
power, the whisk) and beat it 'until it be enough'.  Exactly how long
will change with each batch, so watch it carefully and stop when you
get to the consistency you like.  If you too long you'll find it turns
into lumps which is the beginning stages of butter.  Still tasty, but
not anything like the product you were looking for.

Then, having whipped your cream, stir in a spoonful of Splenda gently.
Taste it.  If it's not as sweet as you wanted, add a little more
Splenda, until you get to the taste you want.  Now you know how much
Splenda it takes to make sweetened whipped cream taste the way *you*
like.

Anything you like. Truly.  Try adding a tsp or so of Vanilla extract
for that classic Vanilla Whipped Cream taste.  

Chocolate is an old favourite - either melt a couple of squares of
unsweetened chocolate (or use Lindt Excellence 85% cocoa, my
favourite) and blend the melted and cooled chocolate into your cream
to make a heavenly chocolate mousse.  You can, if you wish, blend the
melted chocolate into the unwhipped cream to make a ganache, then whip
the ganache.

Try crushing or pureeing some berries then blend the result into your
whipped cream.  A lovely fruity flavour!

You could even try blending a tablespoon (or more, as you like) of
your favourite Da Vinci Sugarfree syrup to whipped unsweetened cream,
too.  Easy and fast, just keep tasting as you did when adding Splenda
to get the taste and sweetness you desire.

Aramanth

Place the cream and 2 - 3 teaspoons of sugar-equivalent sweetener.  Whip
gently until soft peaks form and the cream takes of the consistency you
want.

For a snack, I sometimes whip up some cream, sweetener and a tablespoon of
cocoa to make a chocolate mousse.

Tara

I have one suggestion in addition to other advice that you've received:  The
cream whips much faster, easier and to a better consistency if you chill the
beaters and the bowl in your freezer before whipping the cream!

When I whip cream, I use a half pint of cream, and add 1 packet of Splenda
and 1 capful of vanilla flavoring, and whip in the chilled bowl with the
chilled beaters until light peaks form.

The easy way to make whipped cream (with or without various
flavors) is to use one of those dispensers with a gas cartridge.
You just pour in the cream, add some Splenda (or flavored
sugar free syrups like Torani or Da Vinci).  Then you just
dispense the stuff.  No whipping or mixing or chilling. The
result is very light and fluffy as well.

Here's a link:
http://www.creamright.com/Merchant2/merchant.mvc

Alan