Linking tables -probably quite basic!

[BadgerLikeSpeed]

Hi,
Hopefully there will be a simple solution to this problem...
Due to outside constraints on my design I have a set of databases from external sources, all with the same tables.
Currently I have them all as linked tables in my master database, but what I want to do is take all of the data from tables with the same headings and pull all of that data into one table.
I'm very new to Access, and am learning as I go along, so please answer in basic terms!
The tables contain a list of job times, locations, and other information. The headings are the same throughout, but the jobs do not necessarily take place at the same times, although sometimes they do.
Hopefully that makes sense, and someone will be able to help me out...
Thanks
Phil

 

[BadgerLikeSpeed]

And I have googled it, but couldn't find an answer. If I've missed something obvious I do apologise!

 

[BadgerLikeSpeed]

Can you see the ongoing thought processes?
So now I've worked out how to append data to my master table... But how do I only add entries that have not been previously added? Rather than having to delete everything and then add all of the data again.