Make WordPress template from existing layout+CSS

Hi, I have a website based on pLog and I'm gonna move to WordPress: www.bananamecanica.com.br. Now, I have the layout based on pLog style and a CSS ([login to view URL]). Some things are not tableless nor the best way to go, and turning it more W3C friendly would be a good thing. There are five different blogs (discos, shows, notícias, especiais and agenda), that are different sections of my music-related website. I'm using an unusual way for different kinds of content go to the homepage: there is an rss parser that's getting content from some blogs, and for other kinds of contents I'm doing this by writing on notepad and using an PHP include. I'd like to do all this by using WordPress automated ways. This template has to be compatible with the last WordPress versions and I need to be able to use WordPress' plugins in the main column of each post.