I have to say one letter and you have to name a breed of cats that starts with that letter, I'll start

B (look at my name for a hint)

Bombay, lol.

T

Tonkinese

N

Norwegian Forest Cat

Y

York Chocolate

A

Abyssinian

American bobtail :D

J

Jaguar

P

Persian

Kimododragon a dit :

Jaguar

P

Jaguar is an ancestor of cats but it is not a breed of a cat.

I

Iriomote Cat

P

Persian Cat!

S

Siamese

D

Dark-colored tabby? (Don't know any that start with D, so.. xD)

A

American Shorthair

R

Russian-blue cat

L

La-perm

O

(( I love cats ~ ))

Ocicat

A

Aegean (I watch Cats 101)

C

Cornish Rex

R

Russian Blue!

S