http://entry.ffxiv.com/alpha/index_en.html
http://entry.ffxiv.com/alpha/index_na.html
http://entry.ffxiv.com/alpha/index_jp.html
http://entry.ffxiv.com/alpha/index_fr.html
http://entry.ffxiv.com/alpha/index_de.html

Pick the region in which your SE account is setup as.