x^x = y means x to the power of x equals y. ^ is a common notation on computers used to mean "to the power of". x^x = y is an equation that cannot be solved in one step. You must use a method that gains accuracy every time you do it. It is very similar to Newton's method of square roots by dividing and averaging. Here is the method:
As you may have guessed, a computer program would be very useful here. Here is the source code for one in QBASIC:
You can download the executable here which is written in Visual Basic. A computer program really is required in order to get an accurate result.