Some terms to help you search for more information (links will follow as we get permission)
Patient.co.uk - NHS supported website
Specialist Clothing Suppliers
Comfizz (Stoma, hernia, post surgery underwear)
Vanilla Blush (underwear, swim wear, lingerie)
Other interesting links:
toiletaccess.wordpress.com - an intersting collection of post and comments about accessible toilets. There is a link to my blog on the post But you don't look disabled..
There are several groups on Facebook, most are international and all have different rules about what you can and can't post. I joine a few and have removed myself from several as I felt they were very negative.
Two that I particularly like are the Ostomyland page and Ostomy Lifestyle Athletes (a forum for people with stomas who enjoy sport).