I would like to know the name and number sewed onto the jersey of the
FC Porto Argentinian soccer player, Luis (Lucho) Oscar Gonzalez. I
believe he is Jersey no. 8 but would like to know what name he uses on
the back of his jersey.

When Lucho played with River Plate, he wore the #8 with Gonzalez on
the back of the jersey underneath the number.

google search- lucho gonzalez soccer jersey

then to EBAY store with a game used version on sale:
http://stores.ebay.com/Argentina-Soccer

With FC Porto he is also wearing number 8. I am unsure of what is on
back of jersey. One site does say Lucho Gonzalez, but I cannot confirm
that with a pic.

google search- Luis (Lucho) Oscar Gonzalez bio

You have all the information here:

http://www.uefa.com/Competitions/UCL/Players/Player=101675/index.html

Name: Lucho Gonzalez
Number: 8

I have found a pic with your answer (I was wrong)

http://groups.msn.com/luchogonzalez/fotosnofcporto.msnw?action=ShowPhoto&PhotoID=242

here you can see: Lucho, 8.