It looks so beautiful I'm very jealous right now! Doesn't look like it needs panel lining to look pretty. I do wonder, do the red fins on the arms fall off as easily like the older models? (I use to have the first HG kit of EW zero, and those things would pop off all the time )
The place that I got all of my model tools was actually Wal-Mart. My snippers and Xacto-knife are from the fabric section, and my files are from their tool section. All together, it only cost me $15. Very good place to quickly grab stuff.
For panel lining, I bought official panel line markers off Amazon for only $2.50 each
For good tutorials, on YouTube you can go the Gundam.info for the basic details to start building, but there are a lot of other channels that can help too. If you did anything they would disapprove of, don't worry, pretty much everything is fixable.
Also, never be scared to play with them! If it breaks, just buy a new one. Leg, shoulder, or arm joints get loose? Just put a small amount of super, or krazy, glue, evenly cover it using a q-tip, and let it dry for a good half-hour, and it should gain its friction again.
I will say, refining my old finished model kits is probably the most enjoyable thing I do to pass time.