If you want to do it really cheap there are a couple of options. Check around and see if you can catch a deal on either Microsoft Streets&Trips 2009 bundled with a GPS receiver or DeLorme Street Atlas 2009 bundled with a GPS receiver.
They both work well. Which one you choose depends a lot on what you want to use it for and how you like to work (the user interface is totally different between the two).
You can start by downloading the free trial version of Streets&Trips 2009 and see what you think of it. It's fully functional .. no tricks or limitations. It simply quits working after 60 days if you haven't purchased it in the mean time.
You can find the link for the free download in the first message of this discussion ..
http://www.laptopgpsworld.com/2380-review-microsoft-streets-trips
...ken...