I know many reputable breeders have waiting lists but I don't know if they require a deposit or money in advance. I think if you take your time and look at several breeders you will know when you find your dream Yorkie. You may not find it in Texas. There are many good show breeders out there that ship and that costs around $300.
As far as how many shows, usually the shows go in circuits. You may have a group of shows in San Antonio followed by the shows in Houston and then maybe the shows in Dallas (not necessarily in that order). Show handlers usually go to shows every weekend. Myself, personally, I like to just go once or twice a month. That is about all I can afford. Go to
http://onofrio.com to see all the upcoming shows in the Texas area. There are shows just about every weekend somewhere. It just depends on how far you are willing to travel.