From the Home Screen of your Roku device, use the Search feature or the Streaming Channels Search for "Up". Roku currently has "Up Faith and Family" and also "Up Faith and Family on the Roku Channel" and running a 7-day free trial.
Re: Will you be adding UPTV soon, they have the best Christmas movies
Just to add: It's mostly up to the media companies and developers to make something available on Roku. Roku only offers a platform for developers. Outside of their own Roku Channel and Media Player, they don't create any of the channels.