This review roundup covers 10 SEO tools: Ahrefs, AWR Cloud, DeepCrawl, KWFinder.com, LinkResearchTools, Majestic, Moz Pro, Searchmetrics Essentials, SEMrush, and SpyFu. The primary function of KWFinder.com, Moz Pro, SEMrush, and SpyFu falls under keyword-focused SEO. When deciding what search topics to target and how best to focus your SEO efforts, treating keyword querying like an investigative tool is where you'll likely get the best results.
Another excellent guide is Google’s “Search Engine Optimization Starter Guide.” This is a free PDF download that covers basic tips that Google provides to its own employees on how to get listed. You’ll find it here. Also well worth checking out is Moz’s “Beginner’s Guide To SEO,” which you’ll find here, and the SEO Success Pyramid from Small Business Search Marketing.