dr tiesenga il
I had my surgery out of St. Joseph -- I'm not sure if he does it out of Elmhurst. I was self pay too -- if you call the office, Yolanda gave me all of the info very easily: 887-3-YOU-CAN. I believe my total cost was ~17000 (including the consultation and psychologist etc.)
He does do a pre-op diet. It is a liquid diet - it sucks.
The office has a nutritionist and a co-ordinator(they just got a new one, so I'm not sure how he is), so there is support. They also run monthly support groups which I find very helpful.
Good Luck!
VSG on 01/30/14