Keyword Research
What is keyword research? Keyword research is the practice of checking the search volume of particular keywords and analyzing the websites already ranking for those keywords. This is done in order to see how much effort it would take for your website to be on the first page for those keywords. Seems simple enough, right?

Let's get down into it. :D

P.s. if anyone wants to share some more, feel free to post it here :)

SEOQuake - A useful browser add-on that attaches a bar with multiple metrics for websites you're either viewing or are listed in a Google/Bing search. There's a guide for that here.

MozBar - With this browser add-on, you can do custom searches by search engine, view on-page metrics, export the SERP data to a CSV, and much more. There's an overview of that here.

WireFox SEO Toolkit - Great for keyword research. Country specific, and many other SEO tasks.

Keywords Everywhere - Search volume, related keywords, and metrics analyzer. Free keyword tool, very easy to use. Here is a tutorial video for this.

List of article scrapers:
SEO Content Machine
WP Automatic

List of article spinners:
Small SEO Tools Article Rewriter (Free)
Spin Rewrite (Free Trial)
Word AI (Free Trial - also has a free chrome extension)
Chimp Rewriter (Free trial)
Spinner Chief (Has a free version & paid)

Plagiarism checkers:
Small SEO Tools Plagiarism Checker (Free)
Grammarly Plagiarism Checker (Sign up Required)
Copyscape (Recommended, paid but cheap)
Duplichecker (Free but less tested as the other options by myself)

Keyword Research Tools:
UberSuggest - Free
Keywords Everywhere - Free extension
Answer The Public - Free
Google Keyword Planner - Free
Ahrefs Keyword Generator - Free
Ahrefs Keyword Difficulty Checker - Free
Ahrefs Backlink Checker - Free
Ahrefs Website “Authority” Checker - Free

Ahrefs - Paid
SEMRush - Register & Paid

Backlink creation tools:
Ranker X
AutoFill Magic
Kontent Machine
Senuke TNG (Not as good as the above but can still be used).

Backlink checkers (check to see if backlink is indexed):
Ahrefs (Free to use)
Small SEO Tools (Free to use)
Moz (10 free link queries per month after signing up)
Majestic SEO

SEO SpyGlass

Tutorials for the tools listed above:
Rankerx Tutorial 1 & Ranker X Tutorial 2 (Couldn't find anything more recent than these)
Autofill Magic Tutorial
Word AI & Kontent Machine Tutorial