You can always donate by improving the map for your local area. Assuming there aren't a few OCD editors near you that have completely added everything. I just finished cycling every road in my city and have been using the GPS traces from my rides to update OSM when roads, paths, alleys were missing. I got to do a lot of work in a few new subdivisions that don't appear in the satellite imagery yet.
garmin.openstreetmap.nl is a good place for maps. If one of the predefined areas works for you and you don't need a custom region the download queue is very short. The "Generic Routable (new style)" is better than some of the other maps I've downloaded using the default style.
Typically I just generate my own maps though. I made a few tweaks to the style to make certain things stand out better on my Edge 800. For just my province it takes about 5 minutes to generate a map. This week I did one for all of Canada which took an hour and 40 minutes (excluding the 1.7GB download for the raw OSM data).