I recommend this. Start with a condi anenome. They're under 10 bucks; and while they are not good hosting anenomes for clownfish, they help show you how your water quality is. If you can make the condi happy for a month or two, then go for the Bta, long tentacle, or any other good clownfish-anenome. You can even leave the condi in your tank, while clownfish are not likely to host in it, it still adds color and movement and looks cool.
I also suggest reading up on anenome care including lighting, food, etc... i'm not an expert on it by any means, but I just ahve a 50/50 light from my local store (like $30, so not great but decent), have my anenomes about halfway up in my tank in decent water flow (not directly in line with jets but still get lots of current), and feed them either a frozen food cube or a feeder goldfish (like 10 cents) every week or so) There's lots of tips out there, but if you get a Condi and learn by trial and error you will find what works for you. Good luck!
ps clownfish and anenomes are the reason I got into the hobby as well, I have a successful pair right now and they are fantastic to watch!