
As is sometimes pointed out, and offense sometimes taken, if you really need to ask about how to find a stud for your bitch you are not yet in a position where you should contemplate breeding.
It is important to study your breed (attend shows and gatherings) to see the different dogs, see which dogs are sired by which studs, and how they do in the ring, hwo they are as dogs that you would want to live with.
It goes without saying that you should have a good understaqnding of the requirements fo the breed standard, and be able, or with an expereinced breeders help be able to look at your bitch realistically to assess whether she is of breeding standard, and what her virtues and faults are in order to be able to choose a compatible sirte for the pups.
Your bitch should also have her Hips X-rayed and sent of to the BVA for examining under the BVA/KC/iSDS Scheme for control of Hip Dysplasia. There may also be a requirement for eye testing which shoudl be done annually, and within the year the bitch is mated.
Your bitch of course should be of absolutely unreproachable temperament, neither nervous aggressive or unduyly dominant, and have excellent general health, and should be at least Two years old, and younger than five for a first litter.
Joining the relevant breed club and attending events will be a good place to start, you will be able to meet breeders who may be willing to take you under their wing and teach you what you need to know. Your bitches breeder if reputable (if they aren't then seriously your bitch is unlikley to be breeding material) should be your first contact.
Hope this helps.