First off, buy some KMR and bottles (kitten milk replacer) at
PetSmart/PetCo/wherever.  Start feeding her with the bottle 2-3 times
a day.  Keep doing this until she is ~12 weeks old, and then start
tapering the number and amount of feedings off.  This will help
prevent the oral fixation and seperation anxiety that weaned-too-early
cats often develop.
    Iams is not a good food.  Wet is on the right track -- she is
too little to be able to handle dry food right now.  Leave some down
in case she shows interest, but don't expect much until she gets a
little older.  Foodwise, I would recommend Evolve, Innova, Felidae,
Old Mother Hubbard, or Royal Canin Babycat (a soft 'dry' food designed
for very young kittens).  If you can't find those, Nutro Natural
Choice will do, as will Nature's Recipe.
    If she is still having trouble eating, do a Google search for
'kitten glop'.  This is a recipe (many recipes, actually) for a food
that breeders and rescuers use to help very young kittens gain weight
or to feed if they're orphaned.

    Feel free to email me if you have any other questions.

Orchid

Orchid's Kitties: http://nik.ascendancy.net/bengalpage
Orchid's Guide: http://nik.ascendancy.net/orchid

I have found that Iams kitten food is not very appealing to kittens. Ive had
around 100 of them in my house in the past two years and I can count on one
hand the number of kittens that would actually eat it.  I would recommend
purina kitten food.  At six weeks she should be able to eat on her own -
kittens usually start at 4 weeks.. I have a set that started at two.  KMR is
a great supplement, but at this point if you feed it to her it could cause
diarrhea.  Your right that milk isn't the best food, but its better than
nothing.  If she wont take to a different brand of kitten food, try mixing
the milk in with the kitten food.  Wean her off it quickly though.  Giving
in to their requests for foods that aren't good for them will only spoil
them to not eat the right foods :)

At this age, let her eat what ever she wants.  Ive always free fed dry food
to my fosters.. and gave two feedings of wet food to help them put on
weight.  Id recommend letting her free feed for the first year, then start
scheduled feedings.

Good luck!!