"linked tables:" recommendations

I'm new to Access (Using Access 2003) and would appreciate recommendations on
the method to use to do the following. (..the cleanest, most effecient way to
do this.)

My users will be importing a new csv table weekly. This table will include
records with the clients names and soc sec numbers.

My users will add information to each client. This information (fields) is
not included in the original imported table. These fields include clients'
birthdates, phone numbers etc. This part I have done. (They import into a
table alread in the db that includes these xtra fields.)

Now I need to allow users to add, with a form, a list of multiple items to
each client: They will be keeping track of the client's attendance on a
daily basis. So this seems like it should be a seperate table assigned to
each client. I don't know in advance how many clients will be included in
that imported csv table so these 'linked tables' have to be created
automatically.

It will look like this: User finds the client with a form, sees how many
days he has attended this week and can add today's date to that client's list.

How best to do this?

Thanks much.