Search Engine Journal posted “7 Overlooked Sources of Keyword Data” you may find useful.
Some of these I’ve mentioned in previous posts, however here are a few you may not have played around with yet:
“Technorati is a blog search engine – and a great way to research the blogosphere overall or just find some new sources. Their tag section represents ‘popular tags used on Technorati.com over the last month.’
Browsing here is a good way to find out what topics are buzzing in the blogosphere lately – and, more importantly, what language is being used. You won’t find volume data here, but it’s a great place to look when you’re brainstorming keyword lists.”
“While Twitter isn’t exactly a microcosm of the online population (think demographics) the real time stream provides a good study of the topics of the day and the language people are using to discuss them.
There are quite a few Twitter tools out there that you can use to monitor the buzz surrounding keywords (or find new ones). Here are a few worth looking at:
TweetBeep – think Google Alerts for Twitter – monitors keywords for you and notifies you when they’re mentioned
Trendistic – allows you to track keyword trends in Twitter (with nice graphs that visualize the data)
TweetVolume – see how often your keyword(s) appear on Twitter”
I’d also add Twitterati and What the Trend to this list.
Happy keyword hunting!