You could also get by with a 7810 fixed regulator if you can find one.

I'm surprised that your local RS doesn't stock an LM317T; it's one of the few regulators that many of them do carry.

 

If they carry a 7805:
http://www.radioshack.com/product/index.jsp?productId=2062599

you could use that with a pot between the ground pin and GND to build a somewhat adjustable supply.
The 78xx series regulators are vaguely similar to the LM317, except they have R1/R2 built in. The GND pin has a nominal 5mA current flowing out of it to provide regulation.

E=IR, or Voltage = Current in Amperes * Resistance in Ohms.
We know the current flowing out of the GND terminal is about 5mA, and that the nominal output voltage of the regulator is 5v; we want to increase the output voltage another 5v.
So, 5v = 5mA times what resistance?
Re-write the formula to isolate R:
R=E/I
R=5v/5mA = 5/0.005 = 1000 Ohms.

Note that this value is approximate, as the current from the ground pin may vary somewhat. Using a 1k trim pot in series with a 470 Ohm or 510 Ohm fixed resistor would give you a pretty good range of adjustment.

Also, an additional 5mA current from the OUT terminal is required to ensure proper regulation. You could use a simple 1k Ohm fixed resistor across 10v to get 10mA current from the output to ground, which would be more than enough.

 

I think I found a local shop with an LM317. I'll pick that up tonight and see about fiddling with stuff.

 

Sweet, got it working! I used a 100k pot for the flex sensor. Your diagram had it backwards (going down as you bent it). I feel like I understand whats going on. The voltage regulator seems to be a standard if I ever do anything with a car again.

Maybe I'll move onto that memsic 2125 chip lol.