Hi Emily and welcome,
If you are on a budget, you can always start with a free blog at
www.blogger.com. The key is to create a blog on a specific niche/topic that interests you.
A great example is a guy who emailed me once about his blog. He loves the show Prison Break and just decided to build a blog about the show not really expecting much.
After only a month he said his blog gets between 400 and 800 hits per day. So now he's getting more serious about it and wants to generate some more hits.
His blog is
http://p-break.blogspot.com
This is a great example of picking something that you love about that's not too competitive like "making money". (Which so many people do!) He chose something he loves, learned a bit about blog promotion by researching online and suddenly he has a site getting very good traffic. He makes money from Google ads for free.
And let me tell you, 400-800 visits per day for a blog he started in early October is EXCELLENT traffic, and shows you what's possible if you choose a very niche topic you are interested in.
Once you get your feel for how blogs and how promoting works, you may decide to branch out into building your own site. Web hosting is not expensive and usually starts at about $3/month for basic hosting and domain names are cheap too.