I believe the B22 will work with medium format. It's been a long time since I used one, and I only used it for 35mm then anyway. Go to http://www.omega.satter.com/omega.html and click on the Accessories for Discontinued Omega Enlargers at the bottom of the page. The bottom of the next page has a contact for more information.(posted 9243 days ago)This is a very good enlarger for starters. You'll outgrow it eventually, but it will take a few years. If you stick with modest enlargements (say 11x14 and smaller) you may not outgrow the B22 for a very long time. And most of the accessories you get will work with other enlargers (lens, timer, etc.).
Have fun and welcome to the darkroom hobby.