What does it take to make those nice neat line ends like they come from
the
store, and can I do it at home with commonly available stuff. How about a
big, electric soldering iron? Would that do it?

What they use at the boat sto

http://www.heatshrink.com/prod-steinel-hk.htm

If you're got one of those big Weller pistol-grip soldering irons:

http://www.amazon.com/gp/product/B00...28667?n=228013