To find this out is pretty easy. You need to sound out a few sources and then figure out the overall average. I don't mean break out the math, it become pretty obvious by seeing about 10 different banks with four of them offering the same lower rate.
Actually, in between this paragraph and the last, I quickly put up a new page on my website. This was the perfect excuse as I should of done it a while ago. I read this mortgage commentary everyday and it is always right on. It is hands down the easiest and most insightful one I have every read.
Also, when I refianced both times, I used their calculators which work in your local market. Then I tried a couple of their lenders and one I knew personally. He matched their rates (since I had proof) so I got the best of both worlds, the best rate AND using a person I knew.
I just put up a new page on my site for you. Go to http://www.stefanwest.com and select the financing tab (top right). I just built it and it has three links, ignore the first unless you are in SoCal :). The other two are fantastic. One is a mortgage commentary suggesting when to lock and explaining each day how rates are doing.
The other is the quote system which will give you a great idea of what your rates are in your area with contacts if you want them. Pay particular attention to the upfront points versus rates. If you are a strong buyer in terms of $$ down and such, you should be in a fantastic position in terms of rate.
I hope this helps! I am in the real estate business (don't do loans) but this is what I use even with all the people and tools I have. It has always been the most honest evaluation of rates.