So I need to make a two tier cake to serve about 30 people.. I used a 9x3" cake pan to test and i am wondering if should

cut that in half or make another one? Also this is the same for the top layer. I made a 8" cake and wondering if I should half that and fill or make another layer?

Thanks! First time doing a tier....

I'm really not sure what you're asking.  Are you asking if you should torte the layer?  Most of us do.  A 9" round cake, 4" tall serves 32.  You're planning on putting an 8" round tier on top of a 9" round tier?  Honestly a 6" round tier would look more proportional.

Yes. Sorry I didn't know if I should (Torte) the 9x3" But you answered my question.. I haven't decided which size to use on top. I thought the 6" looked not proportioned actually.. I'll figure it out.. Thanks soo much for your response.. I was confused and didn't want it to look to high!

A 6" and 9" is a quite classic combination for two tiers.  In the old days, the "standard" was a 4" difference in dianeter.  Then the "tower" look came into fashion which was a 2" difference in diameter.  I often use a 3" difference in diameter.  

A 1" diameter difference, which is just a half inch on each side, and if you use a border, really just makes a big round block.

Thanks..Gotcha. :)   I'll play with it and trim it down if it looks out of proportion..