I haven't spent too much time with google, but recently customers are starting to tell me they found my site from google. I'm a bit curious as to how far up on the search it is.
Do you have cPanel? If so then you should be looking at AWSTATS, if not then maybe someone else here could recommend a good stats program. AWSTATS will show where your traffic originates from and in the case of SEs what search terms were used. While that doesnt tell you directly what your ranking is it does give you some good ideas. Of course you can Google the terms you see in your referrer stats to check your position.