Everyone needs promotion, every brand, magazine, every product, so if you think of yourself as a product, you will see how important it is to believe in yourself and also have your marketing tools to aside your pursuits. A handbag designer needs marketing material, a painter, a designer, even an auto shop! With or without a modeling agency you might be thinking " how can I get modeling work?"
Well it has to do with your own marketing you are doing of yourself. In an Internet world being discovered isn't as popular as Making It Happen for Yourself.
Well of course there are websites like Craigslist and plenty of modeling networking websites, to look into, but they come with precaution. There are tons of scams out there. The best thing to do is to get your marketing tools, to do your research of print modeing agencies and to market yourself to these agencies that are realistically working with models of all heights. It is easy to get an agent, modeling agency that works with models of all heights, like commercial print agencies. Agencies that work with "attractive real life looking people," and submit them your modeling compcard.
If you don't think you can model, then you shouldn't. Because a lot of modeling is believe in you and having confidence.