I am assuming you're looking for a GUI type of installation right?
If I am trying to retrieve the info on a Windows machine I use
WinSCP, a client that gives you drag-drop features using the sftp built into the pro (should be built it, I never had to pacman it). Before you can access it from outside your home, you'd need to port-forward the ssh/sftp port (
Fair Warning: This will have your plug open to the net so maybe change your root passwd or create a user specifically for sftp connections w/o root privileges). I've even gone so far to change the from the default port due to one day getting someone trying to brute-force their way into my plug, since changing it no un-invited knocks at the door haha.
From a Linux machine I haven't dabbled much into it but I've just ssh'd in (same method as before) and then scp the file that I needed. Of course, this is strictly CLI, so it'll build your linux-fu.
If you never had to forward a port, it's real easy. You'd have to talk to your router's firewall and open the ssh/sftp port for your plug. Again, once you do this you open the door for anyone to come knocking, so either change your password or change your port. Once it is open your port should stay static unless you have a router using a dynamic setup (I use AT&T U-verse box and it opens the ports for individual components using the same IP address).
You could also check out how to run a LAMP server, though I am sure tons more complex, but opens the doors to lots of options. Webmin is another useful tool to check out. Then pick your favorite option. For what I use it for, Samba for network transfers and WinSCP for remote transfers. And welcome to the forums.