I am not a professional electrical engineer, and therefore, please
excuse me if my question is too simple or stupid:

I have an SPI touch-sensor panel: http://www.qprox.com/products/qslide_qt401.php

I need to build a simple circuit that:

1. Reads output from the panel (i.e., which of the 128 panel slider
positions is activated).

2. Turnes ON one of 4 (or more) LEDs in the circuit, depending on
which part of the slider is activated. For instance, if the position
activated is in the range [0, 32), turns ON LED#1, if the position is
in the range [32, 64), turns ON LED#2, and so on.

I need to be able to build this circuit ASAP. If there is a simple
component (or set of components) that I can buy to make this thing
work, that would be ideal.

If I have to build the circuit from low-level components, how do I do
that? It would be great to have a detailed circuit diagram and
instructions...

If I need to use a PC to take the output from the panel and to
redirect the signal to my chain of LEDs in one way or another, that's
alright, but I need to know how I can do this.

To put it simply, the only rule is that there are no rules. I just
need to make this thing work.

I'll look into this more.
This is possible with either a small microcontroller w/ some code to
read/write to the SPI interface.

OR

Some kind of external PCI card with a connection to the chip and some
C code doing the interface.

Depends on your experience.  How much experience do you have in
electronics?  Can you wire things up on a breadboard?  Can you write C
code or assembly?

I do not have much experience in electronics. I do know low-level
things like resistors, capacitors, switches, etc, and I can wire up a
circuit if I have a diagram, but I do not have any experience in
circuit design.

I am an expert C/C++ programmer and I can write in assembly, though I
have not programmed in assebly for years...

Right now I just do not understand why I need to program the panel...
Ideally, I would like to provide it with some voltage supply, and get
7 wires out, each either ON or OFF. This would give me 128 different
positions, and I guess I would be able to go from there...