Ubuntu 8.04 alias "Hardy Heron" is out now!!
You can download it directly from here: http://www.ubuntu.com/getubuntu/download
There is available the Ubuntu 8.04 LTS Desktop Edition, which is supported to 2011
and the Ubuntu 8.04 LTS Server Edition, which is supported to 2013.
Please choose between the 32 bit and the 64bit (AMD and Intel computers) edition.
Have fun! ;)