trade872,
1 point on the e-mini s&p is $50, 1 point on the e-mini nasdaq is $20.
The dollar value of the contract is calculated by multiplying 50 x the index value for the e-mini s&p, or 20 x the index value for the e-mini nasdaq.
For example: if the e-mini s&p is trading at 890.00, then the dollar value would be 890 x 50 = $44,500. If you had a portfolio or mutual fund that mirrored the s&p 500 and had a value of $44,500, you could hedge it by shorting 1 e-mini s&p contract (i.e. for every dollar lost in your fund, you would make one dollar on your short position in the futures).
The amount needed in your account for margin will depend on whether you hold positions overnight or daytrade, and will also fluctuate with volatility in the market. $2,000 per contract sounds about right for daytrading, but you should contact your broker for the exact amounts.