My company keeps customer records in spreadsheets for that given
customer. Each customer spreadsheet has 12 tabs and is named by
customer number ie: OH09001 Doe and kept in a folder of the same name.
I would like to pull most of the data from each customer's spreadsheet
into a single separate spreadsheet so I can track certain information
without having to double enter.

In my customer spreadsheet I have an "information" tab with name in
a1, phone in a5 etc. I also have a "material list" tab with the
quantity of material in A and the item in B.

I want to put this into a spreadsheet like:

Customer name phone
Material Item
0809001 Doe
0809002 Smith

What is the best way to pull the information out from many
spreadsheets without having them open? I have 320 customers so I'm
thinking I need a macro but don't know where to start.

Thanks!