I understand your confusion as there seem to be so many different names that most people have no understanding of.
A good webdesigner/ Graphic designer should be able to help you out with most of these points. If you already have a corporate image ie Logo/colour scheme/ headed notepaper etc then a site/graphic designer should be able to work with you on the creation of a basic design and what you want YOUR site to look like. They are there to assist you. Many freelance webdesigners will be able to cover most of these aspects for you.
SEO is also something that I concentrate on when building a site by ensuring I use correct metadata, page titles and keywords for each page. Linking off to similar site can also help with SEO. Often a well structured site with correct SEO data built in, a sitemap on google and sending in your url to them is the best SEO you can get.
To get a good list does take time but by using these points you should get there in a couple of months.