A bible for SEO followers in these difficult days, However it is rooted in old SEO. We would never buy links or reciprocal links. This said there are lots of useful tools for instance:
Similar Page Checker
Search Engine Spider Simulator
Backlink Anchor Text Analysis
Backlink Summary
Keyword Density Cloud
Search Engine Friendly Redirect Check
Google PageRank Tool
Cloaking Checker
Domain Stats Tool
Domain Age Tool
Keyword Playground
Website Keyword Suggestions
URL Rewriting Tool
Keyword-Rich Domain Suggestions
Alexa Rank Checker
301 Redirect
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