I am not a great mandolin player either; I'm mostly a fiddler. Sometimes I use a mandolin as a travel/practice instrument since it is a lot less particular than the fiddle.
I'm guessing that you are referring to a style of playing that is called "crosspicking," and I have seen some books around---possibly by Mel Bay---about that style of mandolin playing. I have been recently been looking at a book "Fiddle Tunes and Irish Music for Mandolin" by Dan Gelo, which features some pieces in crosspicking style. The book features a CD to play along with, but I won't pretend that I can play that fast. Hope this is helpful.
Hardiman the Fiddler