Many of the tools and resources used by successful SEO experts are actually available for free. Here is a list of some of the most useful.
Google AdWords Keyword Tool - as used by littledetails.co.uk - designed for someone beginning an AdWords pay per click campaign, this tool allows you to research actual search terms based on your seed keyword.
Trellian's Keyword Discovery Tool - sign up for the free trial for your initial keyword research.
Free Keyword Suggestion Tool from Wordtracker - gives the daily search volume for up to 100 related keywords.
Google Analytics - free resource for tracking your website visitors.
Google Website Optimiser - allows you to analyse different versions of your web site to test the best converting page styles.
CoffeeCup free HTML editor - as used by littledetails.co.uk - drag and drop editor with built in FTP.
Page Breeze Free HTML Editor - with both visual what you see is what you get (WYSIWYG) and HTML tag source code modes.
Color Scheme Designer - online tool to help choose your website colours.
CoffeeCup free FTP client - simple drag and drop FTP interface.
FileZilla free FTP client - open source software distributed free of charge under the terms of the GNU General Public License.