If you're talking about corydalis lutea (the common, lovely yellow corydalis - not a bulb, but a perennial) and you lived nearby, I'll tell you to come on by and I'd dig a few up for you. At least around here, they're not hard to come by.

I know the corydalis you are talking about..... really nice stuff!

Brent and becky's offers two types plus a species, but if you want some of the special ones try odyssey bulbs. They have a much larger selection but you have to pay up for the rare ones. If you want to look at some more nice pictures google srgc (scottish rock garden club) and try looking through either the forums or the bulb log.

If you get real ambitious you could always try the NA rock garden society seed exchange for seeds.....

Here is a link that might be useful: nice corydalis pictures