Hi,
as Sherry says, keeping to the same food until your kitten is totally settled is the best thing to do.
When he is settled, zooplus.de have a bunch of good foods. I used Orijen with my two as kittens and beyond, but generally look for a grain free, quality food. Applaws tins of chicken also go down really well in my house - they are smaller than the pouches/tins you get in supermarkets, but are 75% meat rather than 12%:
http://www.zooplus.de/shop/katzen/katze ... tzenfutterCosima treats are good as well:
http://www.zooplus.de/shop/katzen/katze ... ?rrec=true