Hi Rita,
There are many resources out there about
SEO. Try and get your hands on Aaron Wall's
Seo Book for a start.
As for your company's site, there are just too many things to mention (tables/HTML markup/images instead of text/ etc) !
You should pay more attention to how to link to your site, i.e. the designed by link on
Paintshop, Industrial Paint Shop, Industrial/Warehouse Repairs & Maintenance