Making a LM1458 work as a Unity Gain buffer with an input of 0 to 12v output to a digital voltmeter
The answer to your question is very simple, and it comes in 3 parts:

1) you can't do it with that op amp,

2) you need an op amp with rail-to-rail inputs and rail-to-rail outputs, and

3) don't believe everything you read on the internet.

Take a look at the data sheet http://www.ti.com/lit/ds/symlink/lm1458.pdf
At the bottom of page 2 you'll see "Output Voltage Swing". For a power supply of +/- 15 volts, you can't count on getting better than +/- 12 volts. In other words, the output will only drive to within about 3 volts of the negative supply. Does that sound familiar?