how if i wanna learn Portuguese online..?

Hi, I'm Portuguese actually =)

Here's a list of some helpful sites for you to learn Portuguese (most of them are for free):
http://www.bbc.co.uk/languages/portuguese/index.shtml
http://eurotalk.com/pt/store/learn/portuguese
http://cvc.instituto-camoes.pt/guiadebolso/index.html
http://www.byki.com/fls/free-portuguese-software-download.html?l=portuguese%20european
http://www.youtube.com/user/PortugalForYou?blend=2&ob=1
http://www.portugueselearning.com/
http://www.travlang.com/languages/cgi-bin/langchoice.cgi
http://sites.google.com/site/afalarportugues/
http://avaxhome.ws/software/software_type/linguistic_tools/eLearning/rosetta_stone_portugueseurope_level_12.html

On the sources, you'll find 2 online books (I can only post 10 links here).

Good luck :)

(by the way, there's a troll that sometimes likes to thumb down my answers and he has more than 1 account, just so you know... he usually does that to the Portuguese)

you should want to check this one too:
http://tltc.la.utexas.edu/brazilpod/