It's a minor thing, but a very important building block if one wishes to build a transmitter (or indeed an SSB receiver). As a result, I'm very happy to report that I've built a simple working oscillator on a breadboard.
The circuit I went with is the 'B' oscillator in the image – taken from Solid State Design. Nothing too special, but an oscillator none the less that I was able to test with crystals for both 80m and 40m. (Tried with a ceramic resonator but with no success for some reason – simple drop in place of the crystal appeared not to work.)
Having it run in the shack will I had fldigi monitoring the spectrum on my laptop I was able to see it very strongly in the waterfall and also observe the changes in frequency as I played with the capacitance.
Now all I need is to solder one up with an variable capacitor and then start building some other parts (balanced modulator and amplifier being the two next ones I'm excited to build). Hopefully this wont be too far away, but still rather busy and still a bit more organising of my junk box to make this kind of thing easier.