I suggest this topic to contain a list of providers of mills and recommended mills to use on the micRo.

Everyone with good suggestions, please add a reply to this topic!

Ok, I'll start with a few cheap sources:

Grizzly Industrial:
End Mills
Ball Mills


MSC Direct Single Ended Mills (end / ball / roughers)

..and a higher end place:

Harvey Miniature End Mills

Harvey Tool has a lot of miniature end mills...diamond coated, long reach, stub...you name it.

Wow! You weren't kidding, that is quite a selection.

Think & Tinker appears to have a great selection of bits specifically for milling letters all with 1/8" shanks. This is going to be 90% of what I do immediately with the micro, so I may invest in a set of these.

I bought a "8pc Circuit Board Maker Kit" bit from Drill Bit City and the bits look excellent.