Don't use Araldite or Superglue !
For tip rings, just warm the metal sleave with a lighter (take care not to directly heat the carbon) and slip off the old ring with a towel to protect you from the heat. Use hot melt glue to secure a new ring in place and you're good to go.
If you use Araldite, you can't remove the ring next time you break it and you'll have to cut the blank to fit a new one !
For intermediate rings, I usually carry a few single leg guides for emergency repairs whilst travelling. Just cut the whipping on the top foot of the broken guide (cut over the foot rather than the blank to avoid damage) and remove the whipping. Then pull the old guide out with pliers (you might need a bit of wiggling) before doing a temporary fix by sliding a single leg guide into the remaining whipping and securing it with a dab of glue or nail varnish.
For more permanent repairs, you can do it yourself by buying matching guides and threads over the net (remember to use proper thread or the lint will mess up the finish on your epoxy or varnish coating and don't forget that the thread will darken considerably when coated) but for valuble rods, leave it to an expert - it's riduculously expensive in the UK, so I have my rods re-built in Singapore or Malaysia where a quality service can be had at a reasonable price.