*Marqsaynt rubs his jaw* Jeez... try to help some people. Is it my fault that old Commodore 8032-SK would look awesome as a lizard terrarium?
On a "serious" note though, I'm sure a lot of people/organizations locally have old computers sitting around in their basements and would probably love to find someone to take them off their hands (even better if it's someone that actually appreciates the machines). The main problem is just how does the person that wants the computers and the people that want to get rid of them find each other? In the US we have "craigslist" I'm sure there must be some free classifieds service similar where you live... the occasional look at the "free" section may turn up a few under-appreciated old comps and a "Have an old computer collecting dust? Online computer museum always looking for donations!" ad may also get some responses from people looking to clear out a little closet space.
And of course, be sure to talk about it to anyone that will listen...

You'd be surprised how many friends of friends will go "Oh, hey! I have an old computer-y thing... it's broken though, the screen only displays in green. Want it?"
You may be doing all this already but, if not, it could be a nice way to grow your collection at very minimal cost.