Get a help book sage for dummies or something like and get a trial copy of sage for free and tinker around. I set up a dummy company and messed with various features. In all honesty it's not that hard and as you already have a lot of knowledge and know your way around an accounts package you'll have it sorted in no time.
I teach Sage but I'm nowhere near you so that's no good. However, there is someone on UK business forum (accounts and finance section) goes under Weeblyone (or something like that) think her name is Alison who does remote Sage training by using something like Logmein, if you go over there and post you are looking for training, she will doubtless respond.
I am not near you but the company I work for, The Bridge 2 Learning, provide very reasnably priced sage courses. We are are a registered charity and get grants from various places to run the courses.