I feel they all fit, in a way. Jess and Giro were the hardest to pick out.
PicoDevimon - Brain Dobson, in the style of Red Alert from Transformers Armada
Tsukaimon - David Reale, style of Kai from Beyblade.
Solarmon - Melissa Fahn, in the style of, of course, Ed from Cowboy Bebop.
Floramon - Mary Elizabeth McGlynn, in the style of Viximon from Digimon Tamers' US dub
Nami - Michelle Ruff, a-la Yuki from Haruhi Suzumiya. Since Nami is very dry and deadpan in the games.
Kamemon - Steven Blum, in the style of Dr. Riddles from Zatch Bell. (Yes, odd, I KNOW)
Mikemon - Philece Sampler, the style of Mie/May Delgato from Battle B.Daman
Armadimon - Dave Mallow, unsure of the style though.
PetitMamon - Lia Sargent, a mid-way style of Shion from Xenosaga and Milly Thompson from trigun.
Gomamon - Jen Taylor, close to how she does Cortana in Halo.
Giro - Jeff Nimoy, style of Wolfwood from Trigun, but a bit deeper.
Guilmon X - Paul St. Peter, unsure of the style... :\
Neemon - Quinton Flynn, in the style of Kon from Bleach. That or he sounds like Frontier Neemon
Dorumon - Steven Blum, like Guilmon. Only, grunts and attacks since Dorumon doesn't talk.
Jess - Michelle Ruff, in a style between Rukia from Bleach and Zoe from Frontier.
:D