I would suggest this list as the best place, hands down. I particularly
don’t like RentACoder and doubt you’ll find anyone there (or anywhere
skilled with nginx that ISN’T here on this list.
That said, I know C and am learning how to make modules. I would not
checking out a few simple tasks that I could apply as a module/patch and
submit to the list for use or maybe if it’s really good and useful
inclusion in release; however, ultimately, Igor determines what goes
release we can only ask. He has little time, though, so maybe we can
crank out simple things.
Anything at all non-trivial, I would still be willing to work on, but I
would probably want some compensation as my free time is not in high
supply. I would guess most anyone else on this list in similar
myself (knows C, played with NginX modules, wants to learn more) would
willing to work under the same terms.
If nothing else, you can always hone your skills with C and we can learn
to make NginX modules together :).