I am using Sanguinololu with a screw terminal for the power connection however Im not sure what power supply to use. The wiki says 12 volts but nothing about the current. It would need to power 5 stepper motors + the hot end. What power supply would I need to power this?

The cheapest option is to get a used computer power supply. You need ~ 2 amps per stepper, so 8 amps (z shares stepper driver), plus your hot end and bed if you use one. I would say ~10 amps bed and maybe ~5 amps for the hot end.

Here is a conversion guide:
[www.wikihow.com]

Ah thanks. I don't have a bed so total 13 amps. Finding a computer psu should be easy enough.

You want to make sure that it has enough power:

Watts = Amperage X Voltage
Watts = 13 Amps X 12 Volts
156 Watts

Anything not in a "minitower" size should give more than that. I think my newest PSU does 500W.

If I get a psu that supplies something like 300 watts will that cause any issues (ie too much amperage causing the whole thing to catch fire)?

No, just follow the guide and use a few of the yellow leads for 12V and a few black for ground. You will need a sandbar style resistor to hold a load to make sure the power save feature doesn't turn it off when low loads are present. An an on/off switch is also nice, but you can just plug or unplug it and join the green and black with a twist cap or solder.

Awesome. Thanks for the clarification.

Actually, the power required to run a printer without a HPB is 12V at 5A.

I use a laptop style 12v/5A power brick that I picked up off eBay for < $10 shipped to run my printer without the HPB. I've run it for dozens of hours like that since getting it about a month ago. It barely gets warm.

It's very much nicer, cheaper and smaller than a computer power supply, and it's totally silent.

The one I got plugs into a Radio Shack type N coaxial power jack (5.5mm x 2.5mm) and I posted a bracket on Thingiverse to hold one of them. It's pretty nice and clean.

Nice. Might try that in version 2.0 of my printer because the PC psu Im currently using is pretty big and noisy.