What sort of tax should I register for as an independent IT contractor?

You are already registered as an individual taxpayer, but would also need to register as a Provisional Taxpayer due to you not earning income from one source only.

If your net earnings are above R500 000 you could consider registering a company which may lower the tax burden all all your income.

So where do I start being tax compliant?

You need to register for a tax number with SARS and thereafter will need to complete 2 Provisional Tax Returns per year and a final tax return each year.

Final returns are due by November at the end of the tax year which runs from March - February and provisional returns are due in August and February each year.