Downloading Mac OS X Lion to USB drive on PC

I was given a MacBook Pro to use after the earthquake. I dropped it during an aftershock and it froze up and couldn't find the OS after I restarted. I managed to get to Disk Utility but in my poking around I wiped the drive. The reinstall option in Disk Repair keeps failing. I bought a licensed copy of Mac OS X Lion because that was what it was asking for, intending to format a USB drive to Mac, put the installation disk image on it, and reinstall from that but I don't have a download link, just a redemption code for the Mac App Store that I can't access. How do I get a Mac OS X install image onto a thumb drive when I don't have a working Mac, just access to emergency PC laptops?