Machine Down

So, my home desktop machine's power supply seems to have finally given up the ghost. It was giving trouble for some time, occasionally overheating, resulting in the machine freezing and refusing to start until the power was disconnected and reconnected. Now, however, the machine is not booting at all, and when the power is reconnected, there's a momentary very high-pitched whine from the PSU. Well, I'm hoping the problem lies with the PSU, anyway, rather than the hard disk, because that would suck.

Looking at the thing, though, I'm not altogther confident of being able to put a new PSU in - there are a hell of a lot of connections, and I have little to no idea what any of them do.

So either of two solutions come to mind - I can get someone else to put in a new PSU for me, or I can look for a different shell. Essentially, what I need for case two there is to get hold of a machine which has a working PSU and motherboard. I can then transfer the hard disk, video card, and any other bits I can get hold of from my own machine across to that. I don't know how transferrable the RAM is, so ideally the machine would come with a gig or so onboard.

I should also, of course, consider buying a whole new machine, but that will have to wait for a while.

So, anyone able to fit a new PSU? Or, anyone got a PC they're not using? Motherboard, PSU and ideally some RAM.