I had to get fingerprints done for an ATF transaction this week and after trying the bureaucratic Farifax County PD, I found an easier way to get them done. I'd already gotten the fingerprint cards from the ATF for free using their ordering system so I'd hoped to find a police officer that wouldn't mind getting my fingers dirty. It turns out that the FF PD is bothered enough by these requests that they have a department wide policy.
The sergeant at my local substation told me the PD could only do them at the police annex building in Fairfax between 8-4pm and at a cost of $10 for the 1st card, and $5 for each additional card. But, on the way out, an officer told me that the George Mason University Police Department would do them anytime, for free.
And they did. I went over just after 10pm to avoid the daytime traffic and had them printed up in a few minutes. They even have a new inkless system that outputs the prints to a laser printer so there was no mess. They are at 4400 University Drive, Fairfax, VA, Non-Emergency (703) 993-2810.
So, if you're looking for an LE agency to do your fingerprints, don't overlook any universities that might be close by. If you're near a large college, they may have a fully accredited police department that will help you out.