Im making a two tiered cake. 8 in and 6 in round. Do I need to use dowels? This is my first stacked cake... i read in a PP about straws.. Do those work better?

Either will work, but you definitely need some support under the upper tier.

Ditto - when stacking cakes you will always want some kind of support - straws or dowels will work fine w/ this senario. Straws are a little easier to work with.

I firmly believe that you need to always have support when stacking.