Some photos of Louisiana Creole people from the time period 'Wiley and the Hairy Man' is set in. An interesting thing about the photos is that they're all of musicians.

Creole Slang

Here is a list of Creole slang words to possibly use in Wiley.

'Cooyon' (Foolish, silly)
'Craze-i or Craze-ah' or 'Toekey' (Crazy)
'I'll be a monkey's uncle!' (An exclamation to something you never thought would happen)
'So dirty they could stand up in the corner by themselves' (Used like: "His socks were so dirty they could stand up in the corner by themselves")

Another long list, including proper pronunciation: http://www.experienceneworleans.com/glossary.html

Creole/Zydeco music

Creole music is a kind of music that originated in Louisiana and has a primarily folk sound to it.
Creole music, along with Cajun music, were later developed into Zydeco music or what is known as swamp pop. Cajun and Creole music had a large influence on later country music. The instruments often used were fiddle, according, steel guitars, and some form of percussion.

Here is an example of creole music on youtube
http://www.youtube.com/watch?v=3kFo5aYJI2U

Here are some clips of zydeco music
http://www.youtube.com/watch?v=2xfOyt3VZv0