Jeeze, Mathematica has no cylinder primitives, much less a shell command! I'll have to make my own. Hold on a sec....

Testing... Here are two shells with axes parallel to the y-axis. The second one has bottom centered at (6,5,2), inner radius 3, height 2, thickness 0.5 and is constructed from 50 segments:

You might notice that I have settled for programming shells whose axes are parallel to the y-axis. (Actually, a general shell isn't that hard to program either, as soon as you've had some stuff we do in Calc III.)

Let's rotate the region between the lines y=2x-1, x=0, and y=3-x, about the y-axis So we first sketch the region in the plane. The blue rectangle illustrates the height of a typical shell. The radius of the shell is the distance from the y-axis to this rectangle.

We also need to find the intersection of the lines. It is trivial to do so by hand, but instructive to let Mathematica crank it for us:

So x will go from 0 to 4/3. I'll try to generate a 3-D version:

Here is a 3-D view of the single shell corresponding to my blue rectangle above.

Here's a bunch of 'em.

(Or perhaps you like them with different colors.)