Different voices in DBZ?

I re-watched the Dragonball series, which is one of the few anime series in which I prefer the English dubbed voices over the Japanese ones. Dragonball obviously used the voice of one Christopher Sabat, and had all the voices I was familiar with. I recently started watching Dragonball Z, and EVERYONE sounds horrible, except piccolo (not as good as Christopher's, though) Raditz, and Nappa. Roshi and Krillin's voices were perfect by the end of Dragonball, and their new ones irk me so. So, my question is: where can I watch or download the older episodes of Dragonball Z, with the regulars like Sean Schemmel or Christopher. I've already tried watching Kai, but I prefer the old animation. Please help me.