Google Keyword Tool....just search for it.. It has very good suggestions and the estimate of the number of searches is pretty good sometimes
Using google keyword tool, pick out some keywords which are long tail and seem to have a good number of searches, check out how many other websites are currently ranked for the keyword, then work out what kind of level you are able to work out, if you can take on keywords with 500k+ results, then go for those sort of keywords, nobody can give you advice on that, but if your a newbie to SEO, I'd look for keywords with less then 20k results to start with, once you start seeing some results in the SERP's, move onto harder keywords, no harm in building some stable income from long tail keywords.
You can use Google KeywordExternal Tool. KWS again I find here. What is kws, rainer? means keywords? newbie
how are you in "SEO" but dont understand basic keyword research? I am not in SEO, and have a firm grasp of this concept. Anyways. Try what everyone mentioned above
I recommend Google KeywordToolExternal, but if you want to fiddle around with site keywords and rankings you can try this tool http://www.comjuice.com/keywords/
Use the Google Ad words Keyword Tool. Collect the Local Search volume and global search volume of the keywords & competition. After that prioritize your keyword based on search volume and competition.
Google Keyword Search Tool, combined with Keyword tracker...freekeywords.wordtracker.com/ It is always better to use more than 1 tool to check keywords you want! You will get more accurate results....
Google Key Word tool has to be the best I've found as it gives you estimated monthly on uk and global searches. Stick to long term key words as this will generate a small income and move on to some of the more competitive key words once you have more experience online.
I'll always suggest, Google Keyword tool is best for your keyword research. You can use Word Tracker also for this purpose.
Google Keywords. After that it's pretty much down to the individual. If you think you can take on the top searches then go for it, otherwise pick out some good long tail keywords with plenty of searches. Also a good idea to check the first page of google to see how competitive it is up there!