You can open the product you want training on (Excel, Word etc), then go into the "help" for the product and then search for "training" or "tutorial".
This will supply a list of search results (some on the web) which may be able to help you.
There is also a Microsoft Office "training" web page here that may help
http://office.microsoft.com/en-gb/training/def ault.aspx
You can search on the above page.
For example I searched on "excel tutorial" and got all these "hits"
http://office.microsoft.com/en-gb/training/res ults.aspx?qu=excel+tutorial&av=TRN000