Keyword Selection Tools for Search Engine Marketing (SEM) and Online Pay Per Click (PPC) Advertising
List of keyword research and keyword selection tools for search engine marketing (SEM) through pay-per-click (PPC) advertising.
- Google AdWords Keyword Suggestion Tool
- Overture Yahoo! Search Marketing (Y!SM) Keyword Selector
- Digital Point Keyword Selector Tool
- Keyword Discovery (Paid with free trial)
- Yooter Keyword Selection Tool
- Spyfu.com
- WordTracker.com (Paid with free trial)
- KeywordSpy.com (Paid with free trial)