You can find the health insurance surcharge that your Employer deducted from your wages in Box 14 of your Form W2. However, the requirement for Employers to report this is still being transitioned in, so some Employers are still exempt from reporting this.
Normally any Medical Insurance paid through your Employer is "pre-tax" so you cannot deduct it on your Tax Return. Pre-Tax means it has already been deducted from your wages reported in Box 1 of your W2. This is why you cannot deduct the amount again on your Schedule A.
However, there are some rare instances where Employers withhold after-tax money to pay for your health insurance, so I highly recommend that you double check with your Employer. If your medical insurance is paid with after-tax money, then you will be able to deduct it on your Schedule A.