I have been writing C for 8 years and believe I am fairly good at it at this point. Many of my current projects are done in C, C++, or golang but I know many other languages such as java, C#, and Pic18 assembly. If you want to see some of my more current work feel free to check out my github. Do note that those are all side projects as I don't release source code for most of my paid work.
If that hasn't scared you off then you should make sure what you want me to do meets some simple requirements.The project must be:
I generally handle this by splitting the project into small chunks (generally one to three for an averaged size class in an object oriented program) and plan to spend about a day (6 hours) on them. The chunks cost a fixed pre-agreed amount no matter how long they take so you (the client) essentially get charged per feature rather than how long it takes (since both of us want to keep it from taking long).
You can contact me via email at firstname.lastname@example.org or pm swiley on freenode.(note I may take up to half a day to respond to IRC). Don't feel afraid to talk to me about your idea, I hang out on places like freenode because I love to talk about this sort of thing!