The DfES provides schools with detailed guidance on the use of Electronic Learning Credits (eLCs), including details of restrictions on the use of this funding.
This guidance is highlighted as part of the general funding circular to schools and is displayed on the Curriculum Online website:
http://www.curriculumonline.gov.uk/Helpdesk/Helpdesk+page.htm#tobuy
The information is available in the House of Commons Library.