We have a lot of Janacek's in our family tree. Our Frank Janacek may have been a nephew of your grand parent. I am willing to bet the farm on that these Janaceks are the same as the composer Leos Janacek.
I have read somewhere that one of the earlier Janacek (Veronika) who was married to a Cervanka arrived from Texas but did not like it here. They were older, and they returned back to Moravia. The village they went back to was Hulvaldy which is where Leos was born.
Go to our www page, and at the bottom is a link to join our texasczechs group. You can get a lot of info from the email that goes back and forth. Some of the listers are real nice and will provide stuff from various resources.