how to place auto summary of cells of excel sheets into another sheet/work book?

Hi
New here and self taught on excel so bear with me please.

I have set up a master 'jobsheet' for our business in an excel work book, I then copy and paste this sheet into a new sheet in the work book and rename it as a customer and date. Into these sheets I can put basic info such as date, invoice number, customer name etc as well as more detailed data such as materials used, special requests, formulae driven costings etc. Every new job gets a new worksheet.

I would like to automatically take a summary into another sheet or workbook of all of these sheets as they are generated for new customers, taken from the same cells from each sheet i.e. date from each sheet, customer name from each sheet, etc etc (hope that makes sense)..... this data to appear in the 'summary sheet' maybe five cells wide running in columns down the summary sheet.

Q. Is it possible?
Is it difficult?
How would I do it?

Thanks in anticipation

Eco