Find disk space usage on my Linode

A a good command to find the top size directories in the current working directory would be

du -Sh | sort -rh | head -5

Once you've found the largest folders, you could use

cd /path/to/directory
ls -la

to get a list of the files in the directory along with the file sizes.

I prefer to use the following command, which finds the top ten directories sorted by disk space usage:
sudo find / -xdev -printf '%h\n' | sort | uniq -c | sort -k 1 -n | tail -n10