if I were in Norfolk I would be thinking Popham Microlight Fair at the beginning of May and Spamfield, Isle of Wight, in the middle of June.
Popham is a good day return from Norfolk (we did Rougham from Brimpton in a 503 Rans as a day return) but why not pack a tent and enjoy the comaraderie for a couple of days. Same for Spamfield.
The other real challenge is the annual Blois Microlight do, attended by many Brits, away down the Loire Valley (France!) at the end of August. If you go on this one you will find enough people to show you the ropes (flight plan filing, customs etc) and some one to fly loose formation over the water, which is good for safety. Get your passport up to date and borrow a life jacket.
Andrew.