Aha! Something I know a bit about besides dogs... LOL
First off, good for you for pursuing something you enjoy. Photography can be a difficult business to break into, but making the decision to do it is a big deal. Way to go.
Secondly, I would make your website as uncrowded as you can while still drawing in attention. For example, your galleries for each type of photography (portrait, family, kids, pets, weddings, whatever your headings) really do not have to be all that large. Even something as small as 6-10 well-chosen photos will do. You will want to keep printed portfolios to show interested clients when you first meet with them. These will expand upon what is on your website.
If you can find a photographer to apprentice with, try that. Consider what kind of pet photography you want to do-more photojournalis
tic, casual shots or shots in a studio. Your equipment needs will vary depending on what you are aiming for. Try offering your services to family and friends at discounted rates in exchange for them signing waivers so that you may use the photos of them on your website.
I work a "regular" job and do photography on the side. I mostly work for friends and slowed down quite a bit this past year when I was meaning to pick it up due to job duties for my company. Things are picking up now, though-baby shots, pregnancies, a wedding, a quincinera, etc-which I am excited about. I haven't been pursuing clients as I should have, and the jobs that have come up lately (by referral and people seeing my work) have reminded me how much I love it and want to take it on as my full-time job. To do that, I need to work on the business end. While photography is about pictures, a successful photography business requires more work on the business end.
Also, be sure to consider that weddings and other events are not just one-day assignments. Photos must be sifted through, reviewed, touched up, etc. There are several meetings with clients to factor in as well. This is why you don't receive your wedding photos until weeks or months after your wedding (depending on your photographer's queue).