The resonance frequency can be calculate by the inductance and capacitance across the signal node. Generally, this frequency can be get by w=sqrt(1/LC). If you ask about a resonance bandwith, maybe you refer to a band pass filter. Actually, an oscillator can be consider as a band pass filter with positive feedback.....
You can also plot it on a simulation software and get the f3dBHigh and f3dBLow, to get the band width BW = f3dBHigh - f3dBLow. Remember that your reference fequency is the one at which the output of the filter has the maximun amplitude.