MEN - You will need to buy a tuxedo:  Black pants, black tuxedo jacket (no tails, please), white tuxedo shirt (no ruffles, please), BLACK bowtie and black shoes.  A cummerbund is optional.

There are a large number of websites that you can search to find a very affordable tuxedo. 
Before you go to a store or visit a website, make sure you have the following information:
Your jacket size (42 regular, 44 long, etc)
Your shirt size (16-34/35,  15-1/2-32, etc.)
Your waist size and your inseam

WOMEN:  As of the fall, 2006, all women in all choirs wear the same dress.  This allows women to sing in different choirs without having to invest in a different dress for each choir.  Beginning in the spring, 2007, these dresses can be ordered through the UWSP Music Store, located just outside the choral rehearsal room on the 2nd floor of the Noel Fine Arts Center.
DO NOT ORDER SEPARATELY from the dress company - single orders cost more.

The following sites show the dress style and the size charts for the dress and the jacket. 
http://www.stageaccents.com/products/quickdelivery/page1.html      The dress is the Georgette Dress (black only) in the upper left hand corner and the jacket is the Amadeus Jacket just to the right of the dress.

http://www.stageaccents.com/sections/w_chart.html    This site shows the size charts.  You need to use size chart C for the dress and size chart F for the jacket.
 

PLEASE NOTE:  you must purchase this dress.  No substitutions whatsoever.  The cost will be approximately $101-$105, total, for jacket and dress, including shipping.