BTW Christine, I would second the nomination for contacting Old Town School of Folk Music. Also, I forgot:

Chicago Cultural Center

and

Chicago Humanities Festival

and

Irish American Heritage Center

and

Beverly Art Center

(They do a summer festival, and sponsor the Irish Film Festival)

and

Illinois St Andrew Society

and

Royal Scottish Country Dance Society

All of the above would likely be able to help you get some gigs doing song workshops, and would be culturally in tune to your sort of stuff.