I can’t say it enough – Make sure your WordPress database is being backed-up regularly. Hopefully you never need to use it, but if you do you will be grateful you made the effort now.
I like to use WP-DB-BackUp as it lets you schedule back-ups and have them emailed to you. Depending on the frequency with which you update your blog you can choose how often you want to take a back-up. If you use this plugin you need to make sure you also have a back-up of your theme files/photos and any plugins as this is only a database back-up tool.
I know Back-up Buddy is another very popular back-up plugin that lets you back-up your entire WordPress installation. This is a paid plugin but is worth the money as it makes the whole process pain free.
If you have any questions about backing up your WordPress site or any other WordPress questions send me an email.