Welcome to the forums! We all share a similar story.. but you went to Japan and that beats me lol
I have MP-01 and he is AWESOME!! You will love him. You are starting a bit late with collecting (like i did) so things are gonna cost a lot more than when they were released. The trick is to get your masterpiece as soon as its released. I'm after Red Alert and Shockwave and they are hard to find these days especially for a decent price.
Check out Gumtree, EBay and keep your eyes open around the forums! You will get heaps of info and learn from the crew here
HAVE FUN!