General Excel Sites:

 One of our  favorite Excel web sites,  full of tips, articles, sample spreadsheets and templates. Always worth a visit. Excel consultancy services available.

Excellent  resource providing   alternative  and imaginative solutions to  Excel problems . Suitable for intermediate and Advanced users. Andy also has many solutions for  PowerPoint problems.

This site by David McRitchie is a treasure strove of Excel articles and solutions. Well worth a visit by anybody interested in Excel.