I was wanting to use Audacity, for just recording ideas, as we have a better recording setup elsewhere.

I don't wanna spend much.

I have an sm57 that i would like to utilize.

Could I change the xlr over to 1/8" and run it right into my computer w/o buying some kinda hardware.

I don't plan on adding any other instrument, maybe a few guitars and a drum machine.

I just wanna use it to get down some ideas, and see if some stuff works together.
Just buy a Berhinger Xenyx they're cheap and you can get some mono tracks too. They're like $80 Canadian.