What bird is this?

Anyone help with this one?
Not a very clear image, shot through two window panes but still there seems to be some front-focus (a bit unnerving 'cuz my 30D just came back from a back-focus service check).

Anyhoo,this one took off right after this photo was taken. Had a bit of an attitude as well, scaring away starlings and even a crow that ventured too close. Taken in northern VT.

Taken with a 30D, 200 2.8 + 1.4TC @ 1/800 F/4

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Northern Flicker - a member of the woodpecker family

And it is a male.

These woodpeckers like ants, and so it is common to see them on the ground, rather than hacking away at trees.

Sweet!

Never seen one of these around here before - seen the regular wood hackers, but not these.

Any good online field guides that I can consult in the future?

This guide here isn't bad at all...although you need to know the species you are looking for: http://www.birds.corne​ll.edu/AllAboutBirds/B​irdGuide/

Also check out the sticky atop this bird forum which is all about reference ID sites.