To use MS Query with Simply 2008-2009, you first need to have Simply Accounting running. When you try to connect using MS Query, you will need to supply the server name and port number to use, as well as user name (sysadmin) and password if any is set. If sysadmin as a password, you should know.
The server name is the computer where the SAI file reside or localhost if it is on the same computer you are working on. Port number should be 13540, unless you have more than one company open. To make sure, in Simply, go to About Simply Accounting... and click support info.
You may want to have a look at XLGL, which offers a simpler way of doing all this.
To push data into Simply from Excel, you would need the Simply Accounting SDK and programming knowledge.