Rachel,
If you are exporting to a Word merge, consider creating a Crystal Report for your bill. If you do, there are some really neat things that come from the result, one of which is creating individual HTML documents.
For $58 you can buy Worldmerge which does everything Word e-mail, but it can also attach individualized HTML documents so you can mail XXX's statement to XXX. We have done this with scheduling, Parents' Day info, and other projects. Every time we do something with Worldmerge, I think we should send them more money.
We also have a pricier PDF splitter which can create individual PDFs with file names based on an ID field. Using the Worldmerge program, you can also set it to send these personalized PDF attachments. A little work with CSV files produces incredible results.
Call if you want to pursue this path.
Jerry