Free quantities for shipping cost

I am posting this in the attributes section because I'm guessing attributes will be involved. I must be overlooking an obvious solution.

We have a promotional DVD which we want to offer for free and only charge shipping.

We use flatrate shipping for the items and because there are other items on the site, we can't easily fiddle with weights and shipping costs. We generally use table rates and have a few tiers of prices (like up to 2 pounds are $4.60 and 5 pounds are $8.95, etc).

So we figure we can ship 1-2 for $1.00, 3-20 for $4.60 and 21-100 for $8.95.

Is there an easy way to get a quantity from the customer and change the above rate based upon the range of quantities that will ship for that price.

I guess the alternative is to make 3 products, for example 21-100 dvd's at a price of $8.95, make the shipping free and have an attribute that asks for the quantity.

I tried attributes but want to ADD a price rather than discount it. (I even tried discounting by a negative mount).

So to review, if the customer buys from 1-2 DVD's the total price charged is $1.00, buying 3-20 the price charged is $4.60 and buying 21-100 costs them $8.95. They are allowed to buy any amount in the ranges above, thus 52 would cost the $8.95.

Did you look at the Table Rate table Shipping Module and try setting it to by Item then putting in your shipping breaks?

I'll try that. Thanks.