I am a resident of India.
I have come to U.S for an internship for 75 days(May 5 to July 18 08) under J-1 visa.
Will I have to pay taxes on the stipend that I'll get from the university?
If yes, how much tax will I have to pay and Is there any procedure for tax refund?

Thanking You.

If the amount is more than $3,500 in 2008, you must file your tax return Form 1040NR-EZ. It is filed after you get income statement Form W2 or any other form in January 2009.
For more on nonresident filing: Your U.S. Tax Return: U.S. Tax Filing Requirements for Non-Residents

What will happen after filing tax return form?
How much tax will be deducted from my stipend/wage?
I don't know anything about the tax system, so I'll be very thankful if you can explain me clearly.

Your income is not subject to Social Security and Medicare taxes for 2 years. So make sure that your employer does not withhold these taxes.
If income taxes are withheld and your income for 2008 is less than $3,500 you will get the refund. Or you can talk to your employer and discuss this with them so that they don't withhold income taxes.

Thanks for the information.
My income is greater than $3500, so tell me is there any chance of tax refund?
Please tell me what type of Taxes they charge and the total tax percentage on the income/stipend/wage if I am in U.S under J-1 Visa.

I assume that the university is a University in the United States.

If so, the stipend may or may not be taxable income. ASK the university to be sure.

If not, then NO tax return is required.

If so, then you are subject to federal and state income taxes. The federal return will be Form 1040NR, because you should be able to deduct your daily living expenses as an itemized deduction, or the standard deduction of $5,450, which is higher.

If the university is India-based, then the stipend is NOT taxable and no tax return of ANY type is required.