This is because you did not download the drivers in ~/download (that is to say the directory /home/guest/download, as ~ is a shortcut for /home/guest in your case) but elsewhere.
When you issue the 'sudo dpkg -i *.deb' command in the /home/guest/download directory it tries to apply the"dkpg -i' command to files ending in '.deb' in that directory only.
So look at where you did download the drivers and put it in /home/guest/download, using the 'mv' command, then go on. For instance, if the drivers where downloaded in /home/you_user_name/Desktop you could do this:
cp /home/guest/Desktop/file_name_1 /home/guest/download
cp /home/guest/Desktop/file_name_2 /home/guest/download
sudo dpkg -i *.deb
Replace e.g. file_name_1 by the name of the first driver you downloaded, ditto for the second one.
[EDIT]Sorry to be late, you can do instead what Repo did propose you, you will get the same results.