From Guangzhou it is easiest to take a bus form Fengcun bus station è³ææ±½è½¦ç« at Kengkou Metro Station. The ride takes about 2 hours and should cost ¥57.
From Hong Kong, you can take a 'limousine' bus from Portland street on your left when you exit Prince Edward metro station on exit C2. As of January 2010, these comfy buses leave at 8:30, 14:00, 15:30 and 19:00. You will pass through Shenzhen boarder station, where you need to get off the bus and walk across customs with you luggage save time by asking the bus attendant for the silly health form you have to submit there, so you can fill it out in advance. Total journey to Yicizhan should take about 4 hours and cost ¥130.
From Macau, take the border crossing to Zhuhai and then find a bus station around 100m to the right along the main road after you exit the border control building. The ride to Kaiping should take a little more than 2 hours and cost ¥70.