You need at least
- A pair of condenser mikes. I am using Oktava MK-012 : they are excellent for their price (about 300 € for two in France). An alternative at the same price is Rode NT5.
- An audio interface for PC with integrated preamps and 48 V phantom alimentation required by the mikes. I have an Edirol FA-66, about 300 € in France. I am quite happy with it but, according to some infomation got on the web, the Focusrite Saffire LE, about the same price, has better preamps (which is most important).
- A pair of mike stands and cables, less than 100 €.
- A PC, which you may already have,
- A free recording software, Audacity is OK.
With an electric piano, it's easier. You may connect your piano directly to the audio input of your PC and record it by means of Audacity.
Hope than this can help you.
