Yes, it's the part you were so eagerly waiting for: how much money do I need to bring with me? If your university follows the usual convention, you will be paid only after the first month of service, so for the first month you are dependent on your parents. Rent and the deposit will have to be calculated separately. Apart from that, I recommend you carry $200 in hard cash (be very careful with it and deposit it in a bank the second you open a bank account) and put $800 in a prepaid cash card (SBI does this stuff pretty easily, go with your dad to the bank). With $1000 (excluding rent and deposit), you will be able to settle nicely. This is of course higher than your average monthly expenditure, but that's because of the initial, one-time costs.
You will need to open a Checkings account - that's an account that can be operated with a debit card (a Savings account cannot; both have a;almost the interest rate of the order of 0.01% - not 1%, but 0.01%; this country does not believe in interest). Although every city has its own thing, I would personally recommend Chase, which is a great bank in this Great lakes area, which also has a student account with zero fees; you will need to carry all your documents when you go to them, they're really very nice and will do all the paperwork while you enjoy candy. I also got an ATM card that doubled up as a temporary Debit Card while I waited for them to send me my permanent card, so it was pretty convenient. The only drawback of Chase is that they don't give you checks for free, but to make up they have a great e-check and e-payment gateway and most payments are made electronically anyway.
Do not carry more than $20 in cash with you - it is too risky otherwise. Almost every place accepts cards and electronic money cannot be stolen, at least not at gunpoint. There are some machines that will exchange notes for coins, you might need them for the laundry machine; otherwise, I can't think of a reason why you would need hard cash.
Be responsible with money - this country does not believe in saving a dime, but you should save for a rainy day. Also, you can take a credit card (Chase offers a Freedom card but needs a few months' credit/debit history; a student Credit Union will give you one without any credit history), for which you will need an SSN, but be careful not to ever max out or be late on a payment. If you intend to live in the US for some time, you should build up good credit history ASAP.
8. Other things
Golden rule of America: ask. If you are not sure, just ask; there are no silly questions. Be polite, DO NOT use the 'N' word (nigger) under any circumstances. Illinois is not a very safe state, so be careful while walking at night - avoid dark places and try to move in groups after nightfall. You probably already know all this, but while you live a new life, it's easy to forget, which is why I'm repeating all of this.
For a telephone connection, you will need to team up with people and set up a family plan with a carrier (AT&T works fine for me, some people also have T-mobile). The bill would be around $40/person/mo including data as well as a (free) handset. You could also use your old handset and just get a SIM card. It's pretty easy as long as you have five people. To call India, you can buy a calling card like Vonage. I personally just Skype with parents at a fixed time of the week; you should also get an Internet connection (provider varies by location) at home.
My experience with roommates has been bad so far, so I have no useful advice to give about how to live with them; but in general, I would say 'mind your own business' is a nice place to start. You will get used to the country very soon, it really is not that hard; One thing I will recommend is that you go to the recreation center or get some exercise, because the food here is mostly unhealthy and you will put on a lot of pounds (yes, they use Imperial units everywhere) quickly. And yes, I also go to the gym regularly - they're pretty sophisticated here (indoor, heated pool!). Life is otherwise very sedate, with sitting in front of a computer taking up most of your time. Be honest with your work: failure is not discouraged or ridiculed here, but lying or plagiarism will kill you forever.
Things to get: some warm and light clothing including a light jacket and a towel; your toiletries; optional food packets, some masalas (do declare, put a value ~$10) pillow and bedsheet (optional; discouraged); some spoons; money; all your documentation, kept safely on your person.
Things to do in India: all administrative hassles; learn cooking; learn driving if you don't know already; say your byes to family.
Things to do in the US: buy any cutlery you need as well as toilet paper and paper towels; get your i-card and figure out the local public transit system; head to Walmart and buy anything else you need; IMPORTANT: open a bank account; get a telephone connection.
Things to look forward to: great education, smart people and a chance to live on your own two feet.
This is all I could think of for now. If you need any specific points, let me know. I'm also sharing this on my blog, because it was so much fun to write!
Hope that was helpful.