>This script is very nice to give some info on a table:
>
>

>EXEC sp_spaceused N'dbo.ReportInvoicePivot'
>

>
>What would be a syntax to get the same in one command for all tables from a database?

Check my blog post
http://blogs.lessthandot.com/index.php/DataMgmt/DataDesign/how-to-get-information-about-all-databas

I believe I do have this script there (may be even a few).