Sorry to say you're right- only the first 2 are available in English out of the USA, that includes Kindle. Unfortunately my foreign publisher didn't agree to do books 3 and 4 when the picked up the first 2, so there is a lag. Hoping something gets worked out very very soon though, and the other two will be avail outside of the USA.
There is a movie in the works for Gray Man, and I am sure if that goes forward as planned next year they will publish me.
Great to hear you are enjoying the series. Working on BACK BLAST, book 5 now, and it will be out in the States in November.
Thanks for the reply. I'll just wait till they're available then (kindle)...or maybe I'll just order the hard copies. Anyway, looking forward for the Gray Man movie. I hope it will be one of the guys you mentioned for the lead...not anybody I've read who's interested:)