Fibre washers can be bought at www.woodturningz.com It is in the pen parts page.
I have used contrasting veneers for some of my laminations. Since most veneer is very thin, sometimes I cut up strips, and glue up 2-3 strips together, like 2 dark on the outside and light in the middle.
Sometimes my lamination material comes out of pen blanks. For example, blanks that are too thick for a pen. I just sand one side and slice off 1/16" or so on the bandsaw. Then I sand the cut side.
A glue-up jig comes in very handy. Mine is just a piece of MDF with a straight ledge, also MDF, running along one side, and a stop piece at one end of the ledge. Kind of an "L" shape. I use waxed paper, line up the pieces, put a straight stick on the other side, and clamp away.
Hope this helps a bit.