For the fortune telling, there are lots of ways to go - your kids probably have some neat ideas. The most important key is the person who portrays the fortune teller and how good they are at playing it up. As far as methods, some ideas might be:
1) something like a crystal ball or palm reading where the fortune teller just makes it up as he/she goes along.
2) the ever popular Magic 8 ball
3) Buy a kit/book like Madame Boskey's Fortune Telling Kit (Amazon.com @ about $12).
4) Use one of the games the kids make or do verbally ("cootie catcher", game with steps - list 3 boys names, 3 houses, 3 cars, etc.)
5) Go hi-tech! If you could do it in the library or somewhere with a computer connected to the internet - there are lots of fun sites to hit. The computer becomes the crystal ball:
www.priven.sf.ca.us/fortell.html
kidsinternet.about.com/kids/kidsinternet/library/bl8Ball7.htmwww.ecrush.com/cootie/ec_predicts_main.phtml
www.facade.com/iching/
Good luck!