Q: What I want to know is, can I use the on-line storage with iCould simply to back up files? I have not been able to figure out how to do this.

Currently, only Apple apps (Pages, Numbers, etc.) can back up

data to iCloud.  There is no way to use it to just simply backup any files.

There are some workarounds to get some data stored.

PDFs and any other document that can be read by Preview

can be backed up in iCloud.  Load the document into Preview,

select Export..., click on the directory dropdown, then select

iCloud as destination.  Not a drag and drop solution or an

all encompassing method, but you can get some stuff saved.

Generally no, icloud is not a real storage service, it's primarily for syncing between devices and performing backups from iOS devices to icloud.  As mentioned above, only those apps that have use of icloud programmed into them can use icloud to store data or sync to other devices.  You need to look at Dropbox or Sugarsync.

As suggested, Dropbox and SugarSync are good alternatives, and free at basic level. This page gives some more details and also looks at some other options:

http://rfwilmut.net/missing3