As jules says the breed standard for Yorkies says weight should be 'up to seven pounds'. There is no such thing as a Teacup Yorkie, Miniature Yorkie or Toy Yorkie, they are all just Yorkshire Terriers. Its just that some breeders do not breed correct sized ones, so people think they have to get one of the others to make sure they get a small one. Most Yorkies you see are way above the standard size and if people keep breeding from them then the breed will get bigger, and will start to resemble something totally different.
Try one of the Yorkshire Terrier Clubs, the secretaries should be able to give you a list of breeders who are club members:
�CHESHIRE & NORTH WALES YORKSHIRE TERRIER SOC. Sec. Mrs J. Milner. Tel N: 0151 3273376
�EASTERN COUNTIES YORKSHIRE TERRIER CLUB. Sec. Mrs Pooley. For further information please contact the Kennel Club.
�LINCOLN & HUMBERSIDE YORKSHIRE TERRIER CLUB. Sec. Mrs B Pipes. Tel No: 01904 631961
�MIDLAND YORKSHIRE TERRIER CLUB. Sec. Mrs K Slaney. Tel No: 01283 226189
�NORTHERN COUNTIES YORKSHIRE TERRIER CLUB. Sec. Ms Watson. Tel No: 01226 781373
�SOUTH WESTERN YORKSHIRE TERRIER CLUB. Sec. Mrs J Drake. Tel No: 0117 9601592
�ULSTER YORKSHIRE TERRIER CLUB. Sec. Mr S Larkham. Tel No: 02893 378302
�YORKSHIRE TERRIER CLUB. Sec. Mrs Mitchell. Tel No: 01235 833171
�YORKSHIRE TERRIER CLUB OF SCOTLAND. Sec. Ms Burns. Tel No: 01592 759277
�YORKSHIRE TERRIER CLUB OF SOUTH WALES. Sec. Mrs P Evans. Tel No: 01443 431052