Like Ben, I bought a Garmin on Ebay for around $300. I love it, and even the wife can use it.

She can't use the fancy one I've got on the boat! But, it's a plotter/GPS/sonar. Poor thing hits a button and doesn't know what she's looking at.

I tried explaining Lat/Lon. But underneath, she's a blond.
One thing about all GPSsss (is there supposed to be an apostrophe in there somewhere??) they work good on getting you there, but it may not be the fastest or most direct route. Depending on traffic patterns and small local roads, you may find a better route on a map. So I still print out and carry a map of the area just to make sure Gizmo does have the best route... none of them are perfect, yet.
Oh, one more thing... I pay the $60 a year for traffic adviser. In the ATL, it has saved my arse and re-directed me more than once! It even helped me get around a wreck when we were in Orlando headed to Disney. Well worth it if you travel through any major metro areas.
Ya can't keep trouble from visitin, but you don't have to offer it a chair.