Beginners ressources

Editors

Visual Studio 2010 beta (it includes F#)
Visual Studio plugin (included in the official release, you can download Visual Studio 2008 Shell for free)
Emacs mode for F# (discussion)
jEdit mode for F#
F# support for Monodevelop
SharpDevelop (it has an F# mode)

Introductions and free books on F#, aimed for beginners.

F# Survival Guide (John Puopolo with Sandy Squires) - a free, web-based book aimed primarily at mainstream developers looking to learn functional programming concepts via F#.
F# Programming Wikibook - a collaborative F# book
F# in 20 Minutes - Part I (Chris Smith)
F# in 20 Minutes - Part II (Chris Smith)
Cours F# (fr) (Laurent Le Brun)

Professional F# 2.0 by Ted Neward (planned for October 2010)
http://www.manning.com/laucher/ F# in Action by Amanda Laucher and Kevin Hazzard (planned for fall 2010)
Expert F# 2.0 by Don Syme, Adam Granicz, and Antonio Cisternino (June 2010)
Real World Functional Programming: With Examples in F# and C# by Tomas Petricek, and Jon Skeet (December 2009)
Beginning F# by Robert Pickering (December 2009)
Programming F# by Chris Smith (October 2009)
F# for Technical Computing by Jon Harrop (September 2009)

The following books were based on older versions of F# and are somewhat outdated: