I'm planning to take a trip to Europe and it is very difficult to find halal food over there. Is it permissible for me to eat food (fish, chicken, beef) cooked by Europeons?
The issue is not who the nationality of the cook, but rather whether or not the food falls into the category of haram:
Was the meat slaughtered in a halal way? Kosher meat is considered halal; check the labels. You can also ask the source (on the label) to ask about the method of slaughter. Food labeled halal is also sold in Europe. Sometimes the method of slaughter is not haram, and because most Western nations don't mention anything (god or idol) over the animal slaughtered, it could be acceptable.
Was any pork product used in the production of the food? Sometimes pork products are used as sausage casing for otherwise non-pork sausage, in products such as jello (gelatin) or marshmallows (which aren't big in Europe anyway), or as lard added to bread and baked goods.
Does the product contain alcohol? When cooked long enough, the actual alcohol in wine may evaporate away...but why not just avoid wine-laced sauces, dishes, and desserts?
Usually in Europe as in America one can ask if a product doesn't meet any of these criteria and therefore avoid it. Most people are very cooperative about this. Or you can hang out at restaurants whose owners are Muslim or Muslim-friendly; there are many of those and you can easily find them online.