Have a look at http://jaanus.tech-thing.org/category/half-ohm/ for a very simple two-wire low-ohm adapter for your multimeter. It uses a single 3V cell for power. (you could use USB power if you really wanted to)
That circuit can be modified simply to become a four-wire interface to remove the effect of contact resistance of the probes.
Thanks for that but i need something that is standalone and only reads ohms. This is a project i am attempting to replicate this **broken link removed**
For a simple ohmeter a 1a current source from a lm317 and just a starightforward voltmeter work great, I use one for checking larger contactors and switches.
1A from a usb port might be a little over the top current wise, you could maybe build a 100ma current source then your volt reading would be ohms/10.
You can read low ohms using a pulsed method, but that gets tricky.
This isny much use to you but it gives an idea: