How to extend my visa in UK for few months to take interview

[smzaffar5]

I am on Tier 4 Student Visa which expires on 30 Jan 2015. Presently I am looking for a sponsored job. I have couple of interview soon but I may have many interviews in Feb and March because I am applying to graduate scheme jobs, which take time for whole recruitment process.
How do I extend my Visa.
One of my friends suggested me to go for some short certificate course which will give me chance to stay in the UK for few more months and will be cheap for me. BUT I don't know about any such courses.
Else I have an option to apply to tourist visa and stay few months just to take interviews. BUT I believe I can't apply to tourist visa from within UK.
Any suggestion How do I extend me stay in such a way that if I land a job after few months, I don't have problem to switch to Tier 2 visa.

Thanks in Advance

[smzaffar5]

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