In the past when I wanted to grab a component ( example the gameobject's collider ) and put it into an object variable I would first create a Object variable, then select it's object type by scrolling down that uber long list to find the right component, etc.
I found a quicker way actually, you can just drag the component directly from the gameobject over onto the Playmakeer variables tab.
This automatically creates a Object variable with the correct component type. Nice, quick and easy.
If this is common knowledge already apologies, it was a new revelation to me.