So Google Analytics doesn't show you the keywords that you rank for, or show you the ones people clicked through to your website or what the search term was due to user privacy. But if you head over to Web Master Tools, you can check your search analytics there and it will give you a list of all the queries that you have been shown for, impressions, and CTR.
If you want to check out a keyword tracking tool, the best I've found and highly recommend is Pro Rank Tracker. Where you can monitor keywords that you want to rank for.
Josh's solution is reasonable. If you are really keen, there is an advanced method that uses Excel's vlookup function that can combine the sources to guess what keywords bring in revenue. See this tutorial. I rarely bother with this unless organic search attracts a lot of volume and steps can actually be taken to improve what is learned from the data.