One approach you may want to investigate is the so-called "gyrator",
which is an active circuit that simulates an inductor.  I built one, hm,
maybe 30 years ago, but I would have to look if I can find the circuit
diagram somewhere.  It used standard transistors, resistors and
condensers.  A nice feature of the gyrator is that it is possible to
achieve a very narrow bandwidth (high Q) without oscillation.  Nice for
all kinds of bell sounds.  It is tunable.  I found the following
definition of gyrator:

gyrator filters
===============
Term used to describe a class of active filters using gyrator 	networks.
Gyrator is the name given for RC networks that mimic inductors. A
gyrator is a form of artificial inductor where an RC filter synthesizes
inductive characteristics. Used to replace real inductors in filter
design. 

If I find the circuit and you still need it I can probably scan it in
and e-mail it to you.
Hope this helps.

Job van Zuijlen

Anders Andersson wrote:
> 
> Hello!
> 
> I'm quite a newbie with electronics, but I still would like to try some
> things out..
> 
> For a project I need a *very* narrow BP-filter (fixed frequency, but still
> adjustable so that I could have several modules with different frequency).
> It does not have to be "noisefree".
> 
> Is it possible to construct in many ways, or are there some general rule you
> always use when building BP-filters?
> 
> What would be the best way in this case?
> (I want to know what things I should read moe about, and what I can skip)
>