Hi Tamar,
>I don't know of a site, but I know a little bit about this:
less than you believe <g>

>a score of 100 is considered normal intelligence
and is the arithmetic mean of the scale (top of the bell).
If the test is good, it will divide the population in half.

>a standard deviation is 30 points
nope, 15 points on most scales, 16 on an older one
>a score of 70 is considered seriously impaired
>a score of 130 is considered mentally gifted
nowadays "professionals" use less clear words (especially for the left end)

basic statistics
between 85 and 115 (1 s) are about 66% of the population
between 70 and 130 (2 s) are a bit more than 95% of the population,
so at each end of the bell is then left between 2 and 2.5%.

So if you are past the 3s (>145) you are either
very smart, have cheated or both.

If you have less than 55, either the test wasn't fair for you
(imagine a pure chinese w/o any english skills given an english
[language] test) or you probably wont think much about it.

my 0.02 EUR

thomas