Are jobs available in Poland for English speakers upon graduation?
In civil engineering, not likely. And the pay for entry level positions is very low.
As for going to school in Poland, you get what you pay for. The level of education you would get is lower than in Germany, the UK or, especially, the US, most especially in terms of practical courses. Second of all, Polish universities do not have strong ties to business and industry, so that greatly limits your ability to make useful contacts that will help you in your future career. Last of all, there is little research and development done in Poland, which limits your chances of participating in innovative and interesting research projects.
Another thing is that no one is going to care for you in Poland. You're on your own as a student, unlike in the States where you have plenty of help and guidance. That alone is worth any difference in price.
My advice would be to study engineering in the States. Another thing I would recommend would be to study a high-paid field like petroleum, geological or biomedical engineering. The first two are recession-proof, and job prospects and pay are stellar, especially if you don't mind stints in some harsh environments, desert, jungle, tundra, mines, offshore oil platforms, and the like.
Also, don't forget about state universities in the States. A lot of them have very good engineering programs, and the tuition is low. In the States, cost and quality of education are not necessarily correlated. In any case, get into the best program you can afford, and explore scholarships.
Bottom line, I see no reason for you to study in Poland, or any advantage you could gain by doing so. Polish engineering students dream of being able to study at universities like we have in the States.
As for Germany, that is a real option for graduate school. I did my graduate studies in Germany, and loved it. Undergraduate is another story. Best stick to the States.
