I'm not having much luck prototyping this circuit, I think my problem is getting the correct inductor, I've tried various inductors that I have to hand.

So my question is, what does the inductor do in this circuit? is it some sort of tank circuit?

This is a guitar special effect pedal.
Transistors used are BC109C which are shown used in similar circuits.

 

The original design:
http://www.generalguitargadgets.com/diagrams/wah_847_lo_orig.gif
apparently had a 500mH inductor; that's quite a large one.

Here's a 470mH choke you could use:
http://search.digikey.com/us/en/products/70F471AF-RC/M8408-ND/774948

 

Well, I tried a few more inductors and got it working, the problem is that most of the inductors I have are not marked, except one that is stamped 1.5 H.

But I still don't know exactly what it does in the circuit.