The PC games (The Sims, The Sims2 & expansion packs) are different from the online game. At one time a game package including discs was available in stores, but it hasn't been available for years.
As far as I know the only ways to pay for this game is over the internet, either thru credit cards, paypal (?) or time cards. If they take checks thru the mail, I am not aware of it.