Ari,
You've been given some good advice. Cheap, as in $10-20, iMacs exist and can be found. I live in mid-Michigan, too far to be of help,but I am the volunteer IT support for my wife's parochial school and we still have a few of these. As newer computers enter the lab,the old lab computers displace the remaining G3/G4s in the classroom, and I sell or give them away. (Funds are returned to the school.)
Like I say, too far to be of use to you, but I offer this as an example. There may be schools with these to give away or sell, cheap. College salvage yards are also a possibility. I've had good luck there, as well.
I wish you well - you'll be surprised at how readily you'll get one of these, perhaps without even having to pay for it. Happy computing!
-Doc_Retro