All random generators need a seed number. I use the voltage coming into the power supply on a server.
Say it is 230 volts. It is really 230.XXXXXX volts. That XXXXXX constantly changes in microseconds.
Use the decimal ( or part of it) as the seed number and that is about as random as you can get as it changes every moment.
To each his own. My great-uncle used the U.S. Treasury daily balance.
It depends on how much entropy you need, and how quickly you burn through it. You can also get entropy from user input devices like keyboards and mice, or from a microphone, or from the least-significant bits of the processor temperature, all things which the typical computer has access to. If you really want to get serious about it, you get a special piece of hardware that has a sample of some radioactive material in it, and use the timing of the decays to generate entropy.