There is a good thread on this subject - can't link it - but do a search 'mumsnet juice diet' and google it. There are about 35 pages on the thread so tons of info.
I just started the Jason Vale 7 day diet and am at the end of day 2. I cut out green tea and other caffeinated drinks before starting to lesson the withdrawal symptoms.
The juices are really tasty but I am already tiring of them! However, I think it is just a matter of getting through the days as best you can. He does recommend exercising twice a day on the programme but I haven't done anything as have been too busy. I don't have much weight to lose - really need to tone up more than anything - but I wanted to do a bit of a detox and reeducate my tastebuds. I have a terrible sweet tooth and love biscuits, cake and chocolate........
I had to cheat today as had something on that involved lunch but I chose the healthiest sandwich and had fruit afterwards (and no cupcakes although they looked rather tasty!)
I bought an Omega juicer which was expensive but I intend to juice every day, and my kids (4yrs and 18mo) are also enjoying helping to make them and taste them too. No bad thing given neither will touch a beetroot, celery, green leaves in the raw state but are happily trying them in liquid form!