You can browse over 10,000 free Plugins at www.wordpress.org/plugins
Have a look at the Plugins in several different ways. Browse through the different categories as well as by the most recent or most popular. Try searching with some keywords regarding areas of interest.
Think about what functionality could enhance your users' experience of your site. Write down some of those initial suggestions on a piece of paper.
For example: Do you need a Contact Form? Is it important to you that site visitors can easily and quickly leave feedback, answer questionnaires or get in touch with you at the click of a button?
Is ranking higher up on Google Searches very useful to you for traffic? If so, a plugin to help SEO or Search Engine Optimization would be very helpful.
Do you want visitors to be able to Share your articles, posts or site content on Social Media sites? If so social media plugins can be very useful. These can range from Tweet This buttons on Twitter, to 'Like' this on Facebook. People often include buttons to save your site for future reading using Bookmarking Sites such as Delicious or StumbleUpon
Also think of more complex plugins. For example, do you need a Gallery, to display images, videos or artwork?
Do you need to take payment for selling anything?
That's just a few thoughts to start you off. There are numerous different plugins for different benefits. Have a look and write down anything that you see, or that comes to mind that you think could improve your functionality for your website visitors.
In the Members Area of SelfAssemblySites, we'll be talking you through a number of other plugins and showing you all sorts of ways of deploying them.