In digging around the interweb, I stumbled across two pages (here and here) featuring artwork attributed to Echigoya Shinnosuke. I blogged about him last week and last month, and then I created this Geocities gallery featuring images from a 2005 calendar.
Last night I found G-Project's Echigoya Tatsunoshin page, and it's got to be the same artist.
I haven't found a lot of information on Google, but that's probably because I don't read any Japanese at all. Anyway, here's a G-Project picture.