OMG...I can't believe that the doctor and hospital did not have you meet with one before your banding. I had to meet with the dietitician prior to being approved for the surgery.
Shelly64 has shared some good advice, and is similar to what my doctor's office has told me. The day of my pre-op appointment, I had to attend a 2 hour nutrition education class. Points which were stressed included eating your 3 oz of Protein first, limit carbs to Fiber choices, and nothing to drink until 1 hour after you finish eating. Every bite should be chewed 20 times, and a meal should take at least 20 minutes to complete. If you don't get enough protein nutrition from your food, suppliment with Protein shakes. Protein is priority one.
There are also some bariatric nutrition web sites, however I have found that they mostly are for the by-pass procedure patients, and they have different nutrition requirements.
I am not an expert in the field, I'm just sharing some of the information I was taught in the class I attended at the hospital this week.
Don't get discouraged...stay focused! Good luck!