data entry in excel by linking to other word doc. or excel sheets

this sounds like using excel as a data recording tool question.

i have a client asking me this:

1. when he creates a new order either in excel, how can I help him enter the order in excel data sheet--he wants to include order number, order items (multiple usually), quantity etc.

for example, the order sheet looks like:

invoice # 101

billing address: 123 Center Rd. Shipping address: same as billing

order item quantity unit price subtotal
aaa 1 $10 $10
bbb 3 $20 $60

2. when multiple orders are created in different files (e.g. one order is one unique spreadsheet file), how can I help him update the data entry in the excel spreadsheet by accessing newly created orders?

3. if one order has two or more order items, I hope i can enter the data sheet with two or more rows (meaning that the data is stored at order item level not just order level), how can i automatically create multiple rows for one order?

Sorry these questions sound very rudimentary...I try not to use ACCESS. and i do know how to use excel as a reporting tool once the data are entered.

thanks so much!

Jasmine