I have some waltz songs. Appropriate enough for Black and White ball? You decide that haha. I was just looking up songs that were in 3/4 time signature but I tried to pick out decent ones. Plus I tried to stick with anime/video game music
London 3 (live version) from Professor Layton
http://www.youtube.com/watch?v=Gusmpt5DTlk
Fragments of Memories (orchestral) from FF8 (i think this was suggested already not sure)
http://www.youtube.com/watch?v=iRsxl8pQGkc
Tieve's Theme from Vindictus (it's only piano though)
http://www.youtube.com/watch?v=umPuJxBJD9A
Interrupted by Fireworks from FF7 (this isn't the original though)
http://www.youtube.com/watch?v=ElkrJSFuKc4
On the Other Side of the Mountain from FF7 (not original)
http://www.youtube.com/watch?v=7Qchw8J1at8
To Zanarkand Orchestral Version from FF10
http://www.youtube.com/watch?v=UXLoBe5Ug6o
Zelda's Lullaby Orchestral from Zelda series
http://www.youtube.com/watch?v=EarfJqv-vSg
Roses and Wine from FF8
http://www.youtube.com/watch?v=liNHJMOGCmc
Yuna's Determination from FF10
http://www.youtube.com/watch?v=zBFWEmPytr4
Treasured Memories from Kingdom Hearts
http://www.youtube.com/watch?v=8gYULbtfBrs
Always With Me (Orchestra) from Spirited Away
http://www.youtube.com/watch?v=9JiUwIB-iSw
Futatabi from Spirited Away -pretty song :)
http://www.youtube.com/watch?v=nU8c-Kc4KNA
Chihiro's Waltz from Spirited Away (same as futatabi kinda)
http://www.youtube.com/watch?v=6YfjXdbLjA4
B.T. from .Hack//
http://www.youtube.com/watch?v=ad_L6D9mnj0
Yoru No Uta from Cardcaptors
http://www.youtube.com/watch?v=9Ckd4ylcoA8
[Non-anime]
If My Heart Was a House by Owl City
http://www.youtube.com/watch?v=KubOgjfjL5g
Rainbow Connection cover by Sarah McLachlan
http://www.youtube.com/watch?v=LAEoPKwBJfo