There are many standard SD reports which fit your needs. For accumulated sales data you can use MC+E
and MC+2
which refers to invoiced sales and per-customer aggregated sales correspondingly.

Also you can inspect VC/2
standard report which represent customer fact sheet data including account receivables

What concerns particularly receivables, there is a good transaction S_ALR_87012167
which also includes DSO analysis for receivables as well as evaluation by different metrics.


What concerns the tables, this data lays in multiple tables including VBAK, VBAP, BSID, BSAD, etc., so it wouldn't be easy to grab them manually. You should analyze the code of corresponding transaction to reveal how it calculates the data.
I'd rather stick to extracting data directly from transaction, rather than digging into the tables, as you may just repeat the efforts (aka reinvent the wheel) that SAP put into developing these standard reports.