The Pre-Heresy forum, The Great Crusade, is currently running a squad painting competition which is well worth taking a look at!
More than any other single resource I have to say the Great Crusade has been the biggest source of information and material for my force, and whats more its populated by some thoroughly helpful and friendly guys! If you're thinking of having a go at Pre-Heresy, or even just fancy having a look in the painting section or background stories, then I'd thoroughly recommend pointing your browser in its direction.
Here is my entry for the competition (featuring my commander of the force which I have yet to profile). Apologies for the poor picture quality, it was taken late at night to try and squeeze it within the deadline!
Assault Squad Gabor, led by Commander of the 591st Expedition Leonid:
4 days ago