The very popular Simply Accounting is JET (mdb file format) based. I believe
the actual application was written in VB, but the data part is in fact a
ms-access file. Documentation for all of the tables etc. is included with
the product. If you know ms-access well, then you can write some neat stuff
to open up the simply accounting data file, and grab data. However, I don't
believe it is very practical to insert data from ms-access into the
accounting system directly, as your knowledge of the table structures etc,
and adding of primary keys etc would take too much work.
However, the data is in ms-access format..and can be easily used. The other
day, a client of mine needed a list of "accounts" for a dropdown box. That
"list" of accounts was actually in simply accounting, and I just wrote some
code to "transfer" this data (list of accounts) from the Simply to my
application.
You can download and run the trial edition. (I am currently doing that
now...and like what I see).
http://www.simplyaccounting.com/
There is also "Yes, I can run my business". This is ms-access based, and
source code is available.
http://www.accountingsuccess.com/index.htm
There is also Traverse. This is ms-access based, and source code is
available.
http://www.traverse.ca/