This CD-ROM disk is available for purchase at the Brown County Museum of History.  The museum is open from 10:00 am to 4:00 pm on Saturdays.  Here is part of a sample page of what this collection looks like.  They can't be used as postcards but will give the viewer on his computer a look at Brown County!
 

This is three pictures combined into one postcard.   On the left is the Daniel Baker College; the Center Avenue postcard; and below that, the dam on Pecan Bayou.

Here is a postcard showing Center Avenue in the 1920's or early 30's.  Please note the five-story Brownwood National Bank building on the right.  The streets had not been paved when this postcard was printed.  As Henry Ford noted, a Model T can be purchased in any color, provided it’s black.

The following four postcards of Center Avenue are subtly different.  These photos were taken in the very early part of the 20th Century and shows how active downtown was.

Note the building on the left. Please note how the porch sign changes.  In this postcard, the sign is missing altogether.   In the postcard below, the sign says "coffins."

The "Coffins" sign is shown in this earlier postcard of the same parade.  Furniture and coffins were sold at the same place being as both were made of wood.  Please note Howard Payne College's "Old Main" at the top of the street.

You do not see a "gasoline car" anywhere in the picture.  They weren’t prevalent when this photo was taken. 

The note at the bottom of the postcard reads "Hello Hi!  This is where I spent my Fourth: sure had a good time. Dutch."