Submissions are now open for Volume 4 of 28 magazine, the magazine for painters and modellers dedicated to the Warhammer 40,000 universe in its darker forms.
The article gives you a link to their submission guidelines. Submissions are due be 5 January next year, which is actually quite close.
You can also check out volume 3 of 28 Magazine to see what kind of articles and images they typically print.
If you decide to submit – good luck!