All depends on the wheel tire combo and if you are widebodied or have flares. On my new setup I'm running a 2" billet adapter/spacer that installs to the hub with special lug nuts and also has new hardened lugs installed on the Spacers that the wheel mounts to. If you just want a small spacer you can use a cast aluminum spacer if you need a small amount of clearance.
I am able to provide hubcentric billet Spacers up to 3" wide in any bolt pattern.
eek 3 inches total or for one wheel isnt that getting a lil hairy
seems more likely to break