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I love Ubuntu and I use it since 1985. I decided to download Ubuntu 13.04 but I'm a rookie. If you can send me a CD with that version I would be happiest.
Alternatively, some of the commentators seem to be willing to send you one. You didn't mention how the download failed, but you could also try to download the file again from Ubuntu's website and then create a live USB disk, the link has instructions for both Windows, and OS X.
Canonical do sell CDs/DVDs via there shop but they stopped making these with Ubuntu 12.10 except for LTS (Long Term Stable) releases and 13.04 is not an LTS release so is not available.
The easiest way to get Ubuntu should be to download it. You can get it from here
Make sure you check the MD5sum to check the was no error in the transfer and make a DVD or USB stick to install from.
Instructions on checking the MD5 sum are here