Your best bet is to look into the Access run-time. It's actually the same
msaccess.exe executable that you've already got, but through setting
literally hundreds of registry keys, it's limited so that the users can't
make design changes to the database. Once you purchase the appropriate
package that gives you the license to this run-time, you can distribute it
free to as many users as you like. (for Access 2007, the run-time will be
free once it's released)

Check what Tony Toews has at
http://www.granite.ab.ca/access/developereditionfaq.htm for more details.

You would have to acquire the developers tools for your version of Access
(mostly only 2003 is available right now).  That gives you tools and license
to distribute a runtime of Access to your users.  This cost your users
nothing, but YOU do have to pay for the developer's tools although the ones
for Access 2007 (not available yet) is supposed to be free of charge.

For the older versions that you have to pay for it only makes sense
financially if you have at least several people you will be distributing to.
Less that that and you are better off just buying Access for them.

This is particulalry true if you factor in your extra work and time. An
Access app needs considerably more polish and must be a much more "complete"
aplication to be compatible with the runtime.  You can see how your app runs
by creating a shortcut that opens Access and your file with the /runtime
command line argument.  That will operate identically to what a user with
the runtime would see.

The most notable thing is that the db Window and none of the built in
menubars or toolbars are available in the runtime.  You have to build custom
replacements for all of them that your app requires.