For video tutorials try the following sites:
Exam Solutions – a really comprehensive site with thousands of videos, tutorials and also worked exam solutions for GCSE and A Level Mathematics.
David Smith’s The Maths Teacher site has a great collection of videos for both GCSE (age 14-16) and A Level (16-18). Transcripts are available for each lesson, also exercises with worked solutions. Many of the GCSE videos would also be useful for younger students. There are also videos and written solutions to some legacy A Level papers.
Corbettmaths Videos and Worksheets (and while you are on this site, the 5-a-day resources are brilliant for GCSE revision)
Skills Library-Maths from the University of Leeds has short video clips on a variety of topics.
Khan Academy – an extensive collection of videos.
Just Math Tutorials – another extensive collection
Math Centre Videos – good for older students
Do you know why 153 is in love with itself? Watch this video from Numberphile to find out why.
If you find any videos particularly helpful then why not recommend them to others by using the comments below?
Mathematics for Students 
http://www.youtube.com/user/HEGARTYMATHS?feature=guide
A youtube channel that helps students revise GCSE and A-Level Maths. Also topics are taught in video tutorials – look at various playlists.
Thank you very much Colin – we’ll explore those.