I made a basic list of pen making supplies that you'll need to get started.

Before cutting the pen blank, I like to put a pencil mark across the cut. This allows the grain to be matched up again in case you drop the pen blanks. If I'm doing several pen blanks from the same type of wood, then I'll also letter or number the pairs. Bigger...

Using a 7mm brad point drill, drill a hole through the center of the blank. The brad point drill reduces tear out when it breaks through the bottom. Some pictures of the pen drilling jig are here. Bigger...

Epoxy the brass tubes into the blanks. The brass should be in just slightly from the end of the pen blank. Bigger...

Use a pen mill to square up the ends with the brass tubing and bring the wood flush with the end of the brass tubing. I like to just touch the brass and take a very fine layer off (makes the brass shiny). Once I've done this I put marks on the insides of the tubes (using a permanent marker) to indicate how the grain lines up. One you've turned the pens, your original pencil mark will be gone. Bigger...

The blanks are then mounted in the pen mandrel. There are bushings on either side of each pen blank, and the diameter of the bushing is the "desired" diameter to ensure a good fit with the hardware. The wood chips seem to fly much further than the metal chips, so I use pieces of cardboard to help contain them. The wood turning rest was adapted from a Lee Valley tool rest for the Taig lathe. You can see how I did that here. Bigger...

The fun part is turning the blanks to size. It generates lots of sawdust as can be seen here. For this particular pen, I used a simple design with a flute at the end. Bigger...

Next, the pen body is sanded using 120, 240, and 400 grit sand paper. I use aluminum oxide on a flexible cloth backing, which is really nice for turning. After sanding, the wood is burnished using some sawdust (not the stuff from sanding, but rather the sawdust from turning). Grab a bunch between your fingers and press against the turning wood. This fills in small depressions in the wood, and actually put a bit of shine on the wood. Follow with a a few coats of turners polish. Once the polish has dried, a coat of turner's wax followed by a burnish finishes the pen body. Bigger...

Here are all of the pieces ready to assemble. Bigger...

After pressing the tip on, I like to check to see how far the twist mechanism needs to be pressed in. When properly assembled, a small portion of the straight section of the tip should protrude beyond the tip. Here we can see that the right side of the brass needs to go just inside the end of the body. Bigger...

You can use a vise, or a clamp to press the pieces together. Everything is a press fit, so don't push them too far, since they're impossible to take apart without proper disassembly tools. Bigger...

This is about how far the tip should protrude. The blue stuff at the tip of the pen is some type of coating which needs to be scraped off before using the pen. Bigger...

Here we have the finished pen. Bigger...