Getting to Rio from Sao Paulo

I wasn't aware of this CPF number needed to buy certain airline tickets... is there a way around this?  I need to get to Rio on Thursday (hotel reservation) and my return flight leaves from Rio on Saturday, Sept 13.  Are buses, taxis, rental cars viable options.. or any ride sharing programs out there?  Fodor's says the hotel might be able to help with the CPF number for online purchases.. Thanks for any feedback. 

My first day in Sao Paulo, and it was a little overwhelming.  Weather was great and no crowds or traffic for the most part, but I tried walking to find stuff and the city just goes on and on.  Realizing that Spanish is almost as useless as english when trying to communicate with the locals.

You will have problems purchasing air tickets online without a CPF number, however you can purchase any air tickets at any travel agency in São Paulo without a CPF if paying in cash or credit card.

You can also purchase tickets for bus lines between São Paulo and Rio de Janeiro at Terminal Rodoviário Tietê through Autoviação 1001, Viação Itapemirim, Expresso Brasileiro or Viação Expresso do Sul through their ticket offices at the bus depot and at most travel agencies too, you may also have better luck purchasing online through www.buscaonibus.com.br without a CPF number. Travel time between São Paulo and Rio is around 10 hours so depending on your needs you may want to consider travel at night so you can sleep most of the way there. The buses from each company leave São Paulo on an almost hourly basis, so you should have no problems obtaining a ticket even without reservations at the ticket counter at the depot.

Prices range from R$78,25 (conventional A/C), to R$99,00 (Executive), to R$149,00 (Sleeper).

Thanks very much, again.  I was able to purchase last night online with the help of the hotel.  The bus would have been so much cheaper, I wish I'd seen your answer sooner but I was panicking.  I'm sure Rio will be more than worth it.  Obrigado.