Assuming you have the map repositories set up already in Maemo Mapper, the simplest way is to "download by area". While connected online, zoom and pan so that your area of interest is completely shown in on the screen. You can't stop *exactly* at the state boundaries but you can get reasonably close.

Go to Manage Maps and select to download maps by area in the Setup tab. Pick the zoom levels that you want to download (avoid levels 1-5 as they are very detailed and take a lot of space and also only pick every second or third one above that ... 6, 8, 10, 12, 14, 16. To give you an idea of reasonable detail, I have the whole world at zoom level 16, my entire province at zoom 14, my entire region at zoom 12 and my city and surrounding area at 10, 8, and 6. The area tab is already pre-filled out with the extents of your screen. Press OK.

Maemo Mapper should show a progress bar as it downloads the maps of that entire area for each zoom level. It might be best to start at zoom 10 and only get more detailed maps for specific cities. I find that zoom level 6 gives me street names for everything but the tiniest street.