jbruni87,
as far as I know there's only one way-marked Way between Lisbon and Porto and yes, there is a lot of road walking involved. After Porto you have a choice of three routes - coast, central and inland. The central one is the most popular and tends to be the one followed in the main English-speaking guidebooks. More people are getting interested in the coastal route after Porto and there is a separate section and threads about this nearby on this site.
If you go back though the threads for the last year you'll see that quite a lot of people really didn't like the road walking between Lisbon and Porto and it can be really tough if you also have bad weather. The stages can be long and the albergues few and far between, although this is changing and it's important to get the latest list from the Via Lusitana (also available on this site).
My own experience was that it was a lot of hard yards. In October I got well bitten by mosquitoes, intimidated by unfriendly dogs, pushed off the road a few times by maniac drivers and there were practically no pilgrims to share this with. But you know what? my spirits were nearly always high. The Portuguese people were incredibly open and kind and pretty much restored my faith in humanity (when they weren't driving).
cheers, tom
