strTok function (thread safe, supports empty tokens, doesn't change string)
delimiterFound + strlen(delimiter) sounds like a bug. If the delimiter is longer than one character, *newString will point too far into the original, maybe even beyond the end. Correct me if I am wrong, delimiterFound + 1 is what you are actually after.
Modern C allows, and strongly encourages, to declare variables as close to their use a possible. Consider

char * delimiterFound = strstr(string, delimiter);
....
char * tok = malloc(tokLenght + 1);


etc.
Always test that malloc didn't fail.
More spaces - around keywords, braces, etc - definitely improve readability:

    if (....) {
        ....
    } else {
        ....
    }