After becoming an engineer (and staying in the profession) you can earn anywhere between 35,000 to 150,000$+. Indeed some engineers at google get paid $250000+ at young age... Websites mentioned by Eva above are good ones to look at salaries in different fields..
That being said, money does not equal satisfaction/happiness. Research proves that beyond 75000, happiness does not increase with increase in salary.. something to think about...
It will vary fairly significantly depending on the type of engineer, field of work and experience level. There are a few sites that have typical salaries, ie glass door, payscale.com, salary.com
You have several good responses so far. As noted there as a broad range of salaries, but when I was hiring graduates; engineers (Mechanicsl, Chemical and Electrical) in the chemical industry start at $55-$70,000. Higher pay comes with more responsibility. After a few years of experience, if you are in charge of a major project, manage people/department money you can almost double a basic engineering salary. Travel opportunities and the variety of work are also benefits. But remember......work hard and do a good job and your company will know your value and compensate you accordingly to make sure you don't leave. Good luck.
1. Type of Engineer.
2. What is your desire after being an Engineer? earning more by being PE or PhD? or MBA
3. the path that you take will decide the range of salary.