I've got my filing down to science. I'm usually in on a 10-inch gamer and box roughly 10-15 minutes after the game is over...sometimes sooner. I keep my laptop on for the entire game and type the scoring summary in my box file as they happen. My back up is the play-by-play notes should I have an electronic episode. I type in the names of all the statistical contributors at halftime and usually need only add two or three names at the end. This will undoubtedly save time. I typically write some 6 inches at the half also which most of the time end up not getting used.
I always, always get quotes from game-breaking players and usually on defense since the paper I string for is metropolitan and doesn't keep defensive stats. I NEVER talk to coaches...waste of f--king time and wholly overrated. I've found if you always ask kids about a specific play, after they get through the "It was a total team effort" bull****, they tend to tell you about how they saw it develop, they talk about preparation from film, etc. I love to ask a coach to speak to a player...it burns most of them pretty good. They wonder why you don't want to talk to them first.
As for a stat sheet, I have one in a style that I use as two separate sheets for both teams.
It has about an inch of white space above three different boxed grids of equal measurement. The boxes to the immediate left are large enough to write names and numbers and then the grids move from left to right. Across the top of the very first grid, I have First Downs and then the individual boxes are numbered 1-30. I use the grid below the First Downs for Rushing, the one on the middle for passing and the bottom one for receiving. For each box, I write the yardage and accumulation underneath a slash. At the end of the game, it's easy to see how many carries, passes, pass attempts, etc. as each box is numbered by the First Downs list. To keep First Down's I just circle them. In the white space at the top, I write each penalty, fumble and punt. It takes about 3-5 minutes to total and input everything.
As for filing, I use my Treo as a backup in case I can't get a connection. I just load the file on my small disk and load it into my phone. Then, use my email address to file.
For a stringer, it's important to remain stress free. I hate having to call anything in. Hope this helps.