Mr. J. T. Wijeratne 4S7VJ prepared a complete course for Radio Amateur Exam General class having eight chapters ( It is also available in http://www.qsl.net/4s7vj). You can download these from following links. Some chapters are available in Sinhala language.
Chapter 1 Chapter 1 Singhala
Chapter 2 Chapter 2 Singhala
Chapter 3 Chapter 3 Singhala
Chapter 4 Chapter 4 Singhala
Chapter 5
Chapter 6
Chapter 7
Chapter 8
Zip file containing all chapters
Radio Amateur exam past question papers
Novice Class Download
General Class Download
Other resources