IDEs, Editors, ..

Here are my favorites in descend order

• Visual Studio Express 2012 for Web yes! - it allows you free F# development, notably for libraries
• LINQPad again and again a wonderful tool!
• SharpDevelop sometimes a little bit idiosyncratic
• Online Scratchpad on TryFSharp.org the fastest start …

Additional resources

Maybe the following packages are necessary or in minimum useful:

• Visual F# Express Tools
• The free standalone F# compiler tools
• Windows 8 and .NET 4.5 SDK
• Windows 7 and .NET 4.0 SDK

some (unordered) links

• http://blogs.msdn.com/b/dsyme/archive/2008/04/04/tackling-the-f-productization.aspx
• http://www.fssnip.net/an
• http://fsharp.org/use/windows/
• http://fsharpforfunandprofit.com/