Unfortunately this advice may a bit late for you now, but if you cover the outside of the pots in washing-up liquid before putting them on the fire/wood burner and clean it after use. The washing-up liquid should stop the soot sticking and it should wipe of fairly easily.
This approach is best if you are at a fixed campsite where you can easily wash your pots after use and the extra washing liquid is not too much of an issue. If you are backpacking it means you have to carry a large amount of washing liquid and/or carry sticky washing liquid covered pots neither of which are great ideas.
If you've already got your pots in a mess your options are limited. You'll probably need to do a lot of scrubbing, like you are. If you haven't already soaking your pots in soapy water overnight may help but I doubt it will solve the problem entirely.