Summer Project to upgrade: Powermac g3 or g4

Hey,

Well, im going to have some free time this summer and i need a new mac to upgrade,

I want to buy a PowerMac g3 or g4,
I want it to be cheap (ebay or something), and not to have a lot in it (i need to accumulate some parts gathering dust in the basement)
I have loads of pc-133 memory,
Some IDE cd and hard drives,
The only thing that i would actually have to pay for to upgrade is the cpu.

I eventually want it to be a replacement for my iMac g3 700, 768 ram, 60gig hard drive, tiger,
I want it to be faster than my old iMac,
Heres the questions that are deciding which one i choose,
I want it to be at least 800mhz (preferably at least 1ghz, or at least have the option to go to 1ghz later)
Can i put a g4 cpu in a g3?????
Which has more RAM slots???
(this may be a stupid question, but ive never seen a powermac inside before) If i bought a PowerMac and wanted to make it a dual processor, do i have to buy a certain PowerMac or do they all have 2 cpu sockets?
I have to have a modem (yes, I still have dial up)
Need firewire.
I love to mix the memory (like a 512 and a 256), it makes me laugh at pcs...

I dont want to spend more than $100 on the actual machine, and another $150 on cpu upgrades
Which would get me a pretty good mac considering i have about 1gig of extra pc133, hard drives, cd drives, and even zip drives lying around.



Does anyone know where i can get a PowerMac g3 or g4 for a good price without that much in them?

Thanks a mil in advance,


Tanner.

For your specs and price range, I would say your best bet is going to be your local Craigslist.org page. Just search the computer and electronics listings for Apple, and go from there. I've seen a TON of older Mac computers on my listings of late.

I have no idea, but you may want to tjeck out theese vids first :
http://youtube.com/watch?v=BRJMandDLYU
and http://youtube.com/watch?v=lzebHX01amg
Thoose old macs can be a real b****!