[FONT=Sylfaen, serif]Keyword Discovery Keyword Search Tool,free word tracker keyword search tool.. Those are just the few that i could contribute as to i just used them yesterday. I hope it would be helpful for you as it did much for me... [/FONT]
Seriously. I've found some high-converting keywords that I never found in Wordtracker or KeywordDiscovery (both great tools).
So, let's say you're promoting coffee. After (or instead of) running the normal keyword tools, go to your local Starbucks and take a look around. For example, I had a Venti Joya Del Dia today. Never knew it existed. But, I'll bet folks will begin typing in...
pound Joya del dia
lb joya del dia
buy half lb joy del dia
... before long.
2. Broad match ---> Search Query Report
Run some short tail broad match campaigns on Google (this will take some cash). Bid up to get exposure. Then, after a couple weeks, begin looking through the Search Query Report for those campaigns. You'll notice some words that didn't show up in the keyword tools that will have a good chance of converting.
So, those are 2 methods that I use to get some great keywords.