You should consider invoicing software as well, and I also recommend Freshbooks. Free to use for your first 3 clients.
Dropbox is also great for file sharing. I not only use it to share files with clients, but also with my classmates (I'm a student as well).
You should also consider online backup software to backup your client files. I use SugarSync
and haven't had any problems with it. You get 5GB of free online storage. If you want more there is an extra fee. You want to have a backup in case your harddrive ever fails so you don't lose everything.