Well, I found a M-Audio Fast Track USB soundcard under the christmas tree yesterday

. So far I've used my regular laptop soundcard to record with, with less than desirable results(lets put it this way: The thing could not handle bass frequencies at all and I had to use a distortion pedal to control input volume). I've set up everything today and just started messing around with it. Soundwise it's a huge improvement, I can now hear the lows and highs and everything is much more balanced. I've got two problems though.
1) I can only seem to record onto the right channel. I use the 1/8'' input so I'm assuming this is because I don't have a stereo cable hooked up to it. I'm just not sure though and I would really like to record onto both channels, for panning reasons. How can I do this? It seems like the left channel is reserved for mic while the right is for the instrument input.
2)I just cannot get enough volume while recording. At best I've gotten -10 dB out of it when record īthe bass without any effects. Sure, I can compensate for this but I'd really like a hotter signal and more control over the recording volume.
I'm thinking I need a mixer, so I can use the XLR input on the M-Audio, which does have an input gain control, so I have more control over the input volume and to record in stereo. Is this a right assumption? I'm still quite new to recording so any pointers on how to get the most out of my gear would be much appreciated.