i know this question has been asked a bunch of times, but i would like to ask it again. When i go to google to get the size i need for a fixed road bike for me, i get a bunch of different answers. i am between 5'7 and 5'8 online it says that a 54cm is about what i need. How much different is a 55cm going to be?

https://www.wrenchscience.com/Store.aspx?stylecode=R

click on "Fit System"

WS Recommended Sizes
Frame Size center-to-center:
50 cm
Frame Size center-to-top:
52 cm

does that seem reasonable

if i get the 55cm and it is too long, can i just get a shorter stem, and if it is too high can i just drop the saddle?

go to your LBS
test ride bikes.
let them fit you.

Buying your first bike online makes about as much sense as buying your first suit online.

Or your first wife.

+1 for the "go to your LBS" thing.

i think everything's been said - except bike fit just isn't a function of your height, but also your torso, inseam, arms, etc... just go to the lbs.

yeah but i won't get a bike for the same quality for nearly the same price. Even though the bike is very inexspensive it is not built like crap. I checked one out the other day and i was very plesently surprised