From Osaka to Tokyo Disneyland

Hi Cagen!

It's pretty easy to get there from Osaka, you can take the bullet train directly from Shin-Osaka to Tokyo station.
From Tokyo station take a local train to Maihama, where Disney land is located.

Here is the route in Hyperdia and is it completely covered by the JR Pass.

I hope this helps,
Daniel

PS: Dineyland Tokyo is GREAT! I have always thought it was the best one in the world and they also have Disney sea a completely different park located aside Disneyland.