Your keywords should be the words your customers are searching on. No general list will know that. You know (I hope) what your customers need. So you're the only one who can make the best list for your site.
Say you sell plated square screws (your specialty); then that's a good keyword for you.
I am in search of good site wherein i can get the list of best & traffic oriented keywords for SEO. Yes i want to list my site to the top in any browsers. I need to target my clients & customers. Can you all please suggest me the best sites to choose the keywords. My business is in to Machinery products & handling & creating big jobs for Industrial companies.