I remember there was this place in MUSC that helps with essay editing, citations, etc. I can't seem to remember though, maybe someone can tell me where it is? Thanks

You are referring to the Centre for Student Development, located in MUSC B107.

You can also visit all libraries on campus for referencing help.

The CSD has all those services with workshops and such, check their website : http://csd.mcmaster.ca/ =]

Yes, that's the CSD. If you're lucky, you can also ask your TA to look it over for you... they won't necessarily edit it, but they will definitely give you pointers in making it better.