There is a contextual menu in the Transform component that lets you quickly reset Rotation and Position.
Double clicking on an error that shows up in the bottom of the editor (that red text telling you something has goofed) brings you right where you want to be. 
If you’d like to do “billboards”. . . that is, Camera facing quads, here is what you can do: Create a particle emitter with your texture and blending you want. Set it to “One Shot”, and set the Min and Max emission to 1. Then set the minimum and maximum energy to something ridiculously high, and you’re set.
Happy Unity’ing
-Jon
