* wildcard in.sh script

[Aiza]

I have a directory with files in it. The first 3 letters of the file 
names is the group prefix. I'm trying to write a script to accept the 3 
letter of the group followed by a * to mean its a prefix lookup. But 
when I run it I get a message "NO match" that is not issued by the 
script. Its like * is not allowed as input.

Looking for sample .sh code for handling this standard type of lookup or 
some online tutorial that has sample code for bourne shell programming.

.