How does one get the common PC frequencies (33.33 MHz, 48.000 MHz) from 14.318 MHz?
Well, you can't get exact frequencies from 14.318, but you can get approximations.  For example, 14.318*7/3 = 33.408 and 14.318*10/3 = 47.727.  

You can get closer with larger fractions.  14.31818 * 352 / 105 = 47.99999390476, which is 6.095238 Hz off of 48 MHz with an error of 6/48 = 0.125 ppm.  That's far better than what the crystal will be.  Now, I'm not sure exactly how that ratio would be implemented in the PLL.  I can think of 4 possibilities offhand: VCO of 48 MHz, VCO divided by 352 and reference divided by 105 for 136.363 kHz.  VCO of 240 MHz, VCO divided by 5 for output and 352 for loop, reference divided by 21 for 681.818 kHz.  VCO of 720 MHz, divided by 15 for output and 352 for loop, reference divided by 7 for 2.045454 MHz.  Or VCO of 1008 MHz, divided by 21 for output and 352 for loop, reference divided by 5 for 2.863636 MHz.  

The other outputs would be something similar.  

Edit: Here is a page for approximating fractions: http://www.mindspring.com/~alanh/fracs.html .  If you put in 3.352381378080175 (48/1.31818), it will generate a list of approximations of increasing accuracy.  And 352/105 is probably the most reasonable one, as the terms are relatively small and the result is quite accurate.  Now, doing a two-stage PLL is also possible, but not quite as straightforward as the intermediate frequency has to be selected somehow.