Currently in the UK there are only approximately 70 registered puppies  born each year, with  maybe  an adult registered population of three to five hundred, this can fluctuate a little from year to year but registration levels have approximately halved since around 2007, this is partly due to a lack of demand for a larger hound that requires a lot of work and partly due to breeders retiring, nowadays there are not the large breeders that we used to see years ago. 
Despite the low population the Bloodhound breed in the UK is relatively genetically diverse, there is a steady trickle of imported hounds from Europe and America which have been successfully used to keep the Bloodhound in the UK healthy.

If you want  a Bloodhound puppy you will need to make contact with a responsible breeder, after initial contact the breeder will ask you to fill in a puppy application form, they will do house checks and will ask you questions about your circumstances and how you will look after a Bloodhound, if you satisfy the breeders expectations then you will probably have to go on a puppy waiting list, you will be expected to visit the breeders premises to meet the adult hounds as they are large and boisterous which some people do not expect, there maybe an expected wait for a few years for the right puppy in some instances.

At the age of ten weeks a Bloodhound puppy can weigh 15 Kilos.

Fully grown Bloodhounds can attain the weight of roughly between 40 to 60 Kilos, they are strong powerful dogs so need to be trained well on the lead. They are intelligent, stubborn and sensitive with a strong hunting instinct so if they pick up a scent they will follow it until the end.
Bloodhounds can be expected to attain the age of 10 years old, some reaching 12 or even 13, however bloat and cancer does lower the average age to around 6 years old.