State by state and city by city, find your nearest dog and cat hospital or animal emergency clinic. For example:

Q: I'm looking for the cat hospital in Terre Haute, IN
A: Simple! Just surf to: Small Animal Clinics > Indiana > Terre Haute  

Q: How can I find the cat doctor closest to me in Tulsa, OK]?
A: The "Kitty Dr." can be found here: Small Animal Clinics > Oklahoma > Tulsa

Denver

Bjornsen Barry DVM, 3775 Peoria St, Denver, CO 80239; call: 303-373-4942; located in or near Denver county

Citokirk M DVM, 2658 W Florida Ave, Denver, CO 80219; call: 303-922-5500; located in or near Denver county

Community Pet Hospital, 12311 Washington St, Denver, CO 80241; call: 303-451-1333; located in or near Adams county

Dugan Steven DVM MS Dipl Acvo, 4175 E Iliff Ave, Denver, CO 80222; call: 303-759-0862; located in or near Denver county

Firehouse Animal Health Center, 1038 E 6th Ave, Denver, CO 80218; call: 303-733-2226; located in or near Denver county

Graf Becky DVM, 350 Kalamath St, Denver, CO 80223; call: 303-733-2728; located in or near Denver county

Katz Ken DVM, 4625 E Colfax Ave, Denver, CO 80220; call: 303-393-0510; located in or near Denver county

Kromka Stephen P DVM, 5353 E Evans Ave, Denver, CO 80222; call: 303-757-7881; located in or near Denver county

Martinez Elaine DVM, 4040 E Warren Ave, Denver, CO 80222; call: 303-757-5638; located in or near Denver county

Mile High Mobile Veterinarian, PO Box 460203, Denver, CO 80246; call: 303-394-3189; located in or near Denver county

Richshannon DVM, 1842 S Parker Rd Unit 10, Denver, CO 80231; call: 303-368-4171; located in or near Denver county

Sargent Wayne A DVM, 1454 Tamarac St, Denver, CO 80220; call: 303-377-2779; located in or near Denver county

Tasky Melissa DVM, 2223 S Monaco Pkwy Unit A2, Denver, CO 80222; call: 303-691-3720; located in or near Denver county