Dear Roopa....
TDS on Salary is to be deducted on the normal rates of tax applicable for individuals. As such, there is no Surcharge payable by individuals (and HUF, Firm, etc.) Surcharge is only applicable in case of Companies having income exceeding Rs. 1 crore (Domestic Co. - 7.5%; Foreign Co. - 2.5%)
However, Education Cess @ 2% and Higher Education Cess @ 1% is payable.
TDS on Salary should be computed on the basis of estimated Total Income of the employee after taking into consideration Deductions under Chapter VI A, if any. For more details, you can read Sec 192.