National Geographic does one;
You create a profile and start uploading. The editors choose photos submitted for 'photo of the day' 'editor's choice' and 'my shot'. From there, a photo will be chosen to be put in the magazine.
What is your view of legitimate? You want to get your work noticed by whom?
There are several photo contests here. They just run for fun and for a couple of them the prize is getting to choose the topic and winner of the next contest. There are other contests on the Internet, some even have physical prizes. Kodak is still hosting their picture of the day. If you upload to your gallery here, there is the possibility of having your work featured, although there is no guarantee.
If you are concentrating on portraits of pets and people, and you want your work noticed for commercial gain, you would probably be better off trying to get into the local galleries and trying to get local restaurants to hang your photos. I could be mistaken but I suspect that the vast majority of your customers will be found in and around the twin cities. Your chances of attracting portrait customers from New York, Toronto, Hong Kong, Melbourne or some other far away city are not good due to the time and expense of travel.
You could try this- though it's not really a 'contest', the prize winners are selected by the general populace, most votes wins.
The site talks about a cash prize winner, but I haven't won anything yet (WAAAAA) and the shots I've seen seem to be pretty much run-of-the-mill 'backyard with the kids' shots. Still, can't win anything if you don't enter.
LOL at 'legitimate'. The only oe who can define legitimate is you: do you legitimately want to enter this contest? If you have 'rights' as a photog that you don't want to share, then your job is to read the fine print of all the contests you enter.
I'm not sure sure how entering 'Photo contests' will get you commercial exposure?
If you are shooting portraits and pets you need to target a very local market within reasonable traveling distance if you are not operating from a commercial studio.
You may want to try getting published on sites such as 1x.com which you can then advertise on your website..
I always tend to find these sorts of competitions on Facebook, and I've recently come across a great one!
The luxury hotel Corinthia Prague have launched a photo competition on their Facebook wall where you can win an exclusive break for two to their stunning hotel.
Hope you like it!
Here is a great site with loads of competitions both free and paid entry.
Sign up for their newsletter and they send you updates of all competitions. You don't get spammed and the prizes, even for the free entry competitions are fantastic.
Take a look here Photography Competitions.net
You mentioned you want exposure for your work, a couple of months ago this site featured a competition where part of the prize was a massive billboard in New York would show the winners photo's.
Another part of the prize was, if I remember right was $10.000.
This is just an example of what this site is offering, there are tons of competitions to enter all with great prizes.
Let me know how you get on.
national geographic has contests all the time for free.also they showcase pictures from all over the world by