The damage could be anywhere between minimal and extensive. There's no way of knowing without a close examination of all the components - but you need to know what UNdamaged parts look like in order to determine what IS damaged. You could jack the car up and remove both wheels and start doing a comparison between each component on one side of the car vs the opposite side. Even if you don't know much about the way it all works, you might just see something obvious.

Actually, before you jack it up, what you might do is set the steering wheel so that the undamaged wheel is pointing straight ahead. Then look at the damaged side: Which way is the wheel pointing? Is it leaning inward or outward? This might start to offer clues as to what's bent.

If all else fails, try a reputable alignment shop that can give you a free estimate on the fix. If they understand that you are willing to dump the car if it gets too expensive, they may work with you to only replace what it ABSOLUTELY needs to get it rolling straight again.