Nobody seems to have really addressed this. Yeah, you could totally use a 1 Gallon starter for a 5 Gallon batch of beer. You don't need to pour the entire thing in there, however. Once your starter has been going a few days, pop it in the fridge for another day, and the yeast will settle to the bottom in a nice cake. Then, pour or "decant" off almost all of the liquid, and slosh up the yeast really good before pitching. That way, you're pitching all the yeast propagated from a 1 Gallon starter, but you're only adding a quart or so of liquid to your wort.
This has been addressed countless times. Do a search on it. If you research it enough you'll even get into cold pitching, yeast ranching, and tons of other topics yeast related that are way beyond the OP's original question.
In short, make a large starter, (gallo growlers will peobably work if you can get a stir bar to be stable) Make a stir plate (or buy one) stir starters, or brewers hardware have really decent deals. Make a bigger starter than necessary, chill for 48 hours, decan nearly all of your starter liquid after the yeast has settled, swirl, save some for next time, pitch the rest, done.
Don't make it more difficult than it needs to be, especially if you are just starting out, or getting into liquid cultures.
Fianlly, research, research, research.. look into it, doing a search here will provide tons of forum topics, but then you have to actually read them rather than just ask the question, and get answers you may not be completley satisfied with...
anyhow...everything you need to know is here, and there are planty of members willing to help, but start with
mrmalty.com, by far the best source of starter info online!