Here's Diana, playing with a gadget from Kris Krafter, the Needle Beetle, that selects needles on the LK150, LK140, LK100, or GK370. Diana shows how to do a simple tuck stitch and a simple slip stitch.
If you want a Needle Beetle, they're available at kriskrafter.com.
Diana's blog, diananatters.blogspot.com, has lots of machine knitting information, inspiration, free patterns and free lessons. Diana's books and videos are available at www.dianaknits.com.