It depends what you need to share, and whether the databases are largely independent and just sharing some data, or if all users will be using the same data.
If you only want to share some of the data, you can always link the table from the first database into the second. That way, any changes in one will be reflected in the other. Unless, of course, you have relationships between the tables that require values in related tables as well. If that is the case, link all of the required tables across. You can also import the form and any relevant queries into the second database, so you get the same functionality.
If you don't need the changes to be reflected immediately, and you have several users who will be entering data that needs to be sychronised daily, take a look at database replication.
And, if you just want all users to be entering data into the same database and getting immediate updates, split the database into a front end and back end. Give each user a copy of the front end on their C drive; all of them will be able to see and modify the data in the back end, which should be located on a network drive.