Filling in fields to a partially complete record in a table using a form

[semitac]

I have a access database where I have a table called Parts. The table contains columns ID, Part Number, Manufacturer Name, Manufacturer Part No.

The Part Number column is filled with unique number i.e. SL1000, SL1001 for each record.
The manufacture name and manufacture part no for each record are partially complete.
Say, record 1 to 10 is all complete then record 10 to 20 only the part number is filled and the others are empty.

I have created a form to show these fields in a column.

What I want to do is the following.

1. Click a button, say Add new data. This finds the entry for the first unfilled cell for Manufacturer Name and Manufacture part number.
2. The operator will fill these fields and then click submit. Which will result in the Part Number column to be displayed for the record.

Is this possible in access 2007 or 2010 ?

Currently, if I use add new record, access prompts me to a complete new record.

Thanks

Jay