There are social networking sites that can make you reconnect with former classmates. You can utilize these services. Have friends working in different areas like consulting, business development or anything that is related to banking. You can ask anyone and see if there is opening in the field. If you don’t know anyone directly, then list down friends and acquaintances. You will never know if they know someone in the fields. If you want a job in investment banking then sell yourself. There are high probability leads that would generate more income compared to others.
Another great idea is your alumni network. If you didn’t graduate from a popular university, you would likely to find school mates working in this field. Take advantage of older people because they might get you in the field. Most likely your school has an alumni center. Don’t be disheartened if someone is not replying. If worse comes to worst, you would need to do cold calling. The internet is a best place to find companies with investment banking department. This process have higher success rate. As an advice avoid headhunters. They only go for people with high potential. Remember to be equipped with good resume.