Pronouncing of the "ski" and "ska" part

Being a female, if I were in Poland, would the "ski" part of my last name be a "ska"?

yes

Like that:
Ola Kowalska -she
Piotr Kowalski -he
Rodzina Kowalskich -Kowalscy family
Państwo Kowalscy -Mrs Kowalscy
dom państwa Kowalskich - Mrs Kowalscy's home
:-)

Where did that come from ski/ska? And how can you track down families is last names are diffrent??

is hasn't always been the case. there are families that still keep the masculin form of the last name for all members. it's the evolution of the language that has instroduced this differentiation between men and women in a family.
when you marry you can actually choose the form of your 'future' last name.