1) Use UPC codes. There's an industry standard - if the UPC code starts with "2", it's not a real UPC code, so you can use it, even externally, and it won't cause problems. You will have to create valid codes or the scanner won't read them.

2) Yes, if you want to keep the barcode, you'll need a barcode field. Just make a plain char-type field.

3) How you interface the scanner depends on the scanner. Most of them look, in software, like keyboards, so you just wait for keypresses - there's one for each character and a vbCr at the end. Trap the vbCr (If KeyAscii = vbCr Then) in your KeyPress sub for the control that's getting the barcode (a text box?) and you'll know when a barcode has been entered (or someone hit the Enter key).