http://www.feedmap.net/BlogMap/
FeedMap = Blogs + Maps
Using FeedMap you can geo-code your blog, browse already geo-coded blogs and search for blogs. Once geo-coded, you can get your own BlogMap location using a simple url that allows you to network with your local bloggers and much more!
一応APIもあり。
ま、なんか最近こういうLBSっぽいの多いわな。自分もやってるけどさ・・。