I'd recommend SEOMoz beginner's guide and I think you should also checkout Patrick McKenzie's writings (http://www.kalzumeus.com/greatest-hits/ under SEO).

I was able to use these ideas to create an experiment that doubled my organic traffic (http://whitetailsoftware.com/2013/01/how-i-doubled-organic-s...), but know that some parts of SEO are simply measured in calendar time.