I got x220 core i7. I can either log into Windows once and go to http://goodbye-microsoft.com/ or try the following.
Step 1: Get image files
Since I have network access, I was going to put image files on a usb stick via http://www.debian.org/distrib/netinst#verysmall . However, this page leads to individual files and I wanted to download them all at once. According to Lenovo website, I have amd64 and here's the link that lets me download everything. I don't know why the Debian website doesn't link to this page from the net installation page.
I put the file onto my USB stick.