ValentIna, VAlya, ValyUsha, ValyUshka, VAlen'ka, VAlechka,
Валентина, Валя, Валюша, Валюшка, Валенька, Валечка
copy and pasted from Masterrussian.com
Check out the Russian Bride sites, I've seen sweet talk listed there. Dorogaya (dear) if all else fails. Russian Romance - Johnson's Russia List 2-14-03 is by Michele Berdy from Moscow Times. I can't list my nicknames as my mental health would be questioned.