If, for example, you were a Catfolk attacking with your claws only and you have BAB +6/+1 do you get the secondary attacks because your claws are counted a primary weapons.
So from 2 claws +10, to 2 claws at +10/+5
I think you only get the secondary attacks with actual weapons but I'm not sure. Help!
Iterative attacks do not stack with natural attacks.
So if you have 2 claws, they both use full BAB. You do no get any iterative attacks with those claws.
However, you can use manufactured weapons and natural attacks in the same round. For example, You could sacrifice one claw attack to hold a sword. Your sword would be at +6/+1 (for two attacks), and then the rest of your natural attacks would be secondary attacks (-5 from your highest BAB, 1/2 str for damage).
Be careful with terms. "Primary" and "secondary" are terms associated with natural attacks. They are not used with BAB or iterative attacks.
Full BAB represents your first and highest BAB score. In this case, the +6. All the other attacks (in this case, your +1) are called "iterative" attacks.
Check out this thread for more examples. This question pops up here an there in the forums, so you can easily find other examples by searching. And notice that while the second poster says it's correct, that poster is soon corrected on his/her mistake.