i guess you want to "sample" the oscillator waveforms?
if that's so, uhm..
well, simply there is no point in sampling the sawtooth as it's pretty much a standart sawtooth
as for the square, it's not so easy
you can't put 1 cycle of the square into a table
the square wave on the 303 (and x0x) is a very odd thing
the "shape" changes depending on the frequency, and it changes a lot, and this is why it sounds so unique
what you _can_ do is to use a cheap approximitation instead
there is already information available you can try stuff out or simply do your own research
for a cheap and fairly good approximitation you need to match the following properties:
1) the pulse width
2) the softness of the softer edge
3) the amplitudes of the edges
all of the 3 things depend on the osc frequency
if you actually want to get inside the x0x (i guess you have a x0xb0x, right?) i've also done this
you can record both waveforms (raw) at the same time by hooking 2 probe clips (Left / Right) to the waveform switch, connected to your PC, and one clip to ground
also, i used 100k resistors for the probe clips because otherwise they mess up the normal behaviour of the VCO
a better option would be if you have an oscilloscope, but i don't have one
there is however a problem with the soundcard recording thing - your soundcard probably has a DC-filter on the input, so your recording won't be "raw" .. it will be the VCO high-pass filtered
you can fix this with an "inverse" filter to a certain point
and btw, there is already a JAVA 303-like synth, it's a standalone app, i can find the link if you want to check it out..
feel free to ask about anything