Create a two cell table. (If you are not sure how to do this, search in Word's help index under "tables , creating").
Type your Art Show information in the left cell of your post card.
Click in the right cell of your postcard and using the Tools menu select Mail Merge. This will bring up the Mail Merge Helper window.
Click on number 1, Main document - Create then select Form Letters and tell it to use the Active Window. (actually, any of the options will work here) Now click on number 2, Data source - Get Data. and choose Open Data Source. This is where you scroll to find the data that will be entered on the postcard. In this dialog box you will need to change the Files of Type setting from *.doc to *.mdb. (Access data bases use the extension *.mdb so you have to specify that's what you are looking for or else it won't show up). Now navigate to the folder that has your Access Database in it, and select it. If you have more than one query, select the one with your mail list in it. After choosing your query, close the form letter setup box.
Word then needs to set up the main document (your postcard template).
Pick the fields for name and address and space the entries within the right hand cell properly.
Take the cell borders out so it looks like a normal postcard.
Save as a new template for that particular show. You can edit the show information next year.
On the Mail Merge Toolbar, select a button called "Mail Merge" (it's a smaller button towards the right hand side).
Word will then pull the requested information from the database and create all your postcards, ready to print.