MAIKO girls are very popular among tourists.  They are undoubtedly a “dream subject” for many photographers, especially for foreign photo lovers.  But the reality is that it is very hard to find them even in Kyoto.  They are a professional entertainer and appear only for special occasions and ordinary people can hardly meet them.  If you happen to encounter them on the street, you should thank for your good luck.  But be careful, they could be  “fake”MAIKO girls; most of them are tourists dressed in MAIKO Kimono.  Dress-like-MAIKO service is one of popular tourist attractions these days.
Last year, I had an opportunity to take true MAIKO photos in Kyoto!  It was a photo shooting session coordinated by a local newspaper office for amateur female photographers.
 By the way, can you distinguish MAIKO from GEISHA?  If you can’t, please check it in Wikipedia in English.  The article about MAIKO is very clear and concise.