[Guy Sherman]
> Would the approach to use a sample-rate converter to essentially interpolate
> samples, then do the processing, and then sample back down?

The principle is indeed the same, and you could use a converter
library for this purpose.  However, those converters are designed to
work over a continuous range of samplerate ratios whereas the ratio
chosen for oversampling is usually a fixed integer because this
presents ample opportunity for optimisation.  The interpolation
filters in both cases are usually windowed sinc FIR (much like the
Lanczos kernel in image resampling).

> How does that work for live streams of data?

As you intuit: you sample up, process, then sample back down, ending
up with one output sample for every input sample.

IIrc, http://quitte.de/dsp/caps.html contains at least two oversampled
plugins and comes with source code.

Cheers, Tim